Lithium ion battery system safety entropy evaluation method and device considering concurrent faults

Abstract

The invention discloses a lithium ion battery system safety entropy evaluation method and device considering concurrent faults, and belongs to the technical field of lithium battery management. The method comprises the steps of determining an accessory fault probability and a concurrent fault probability of the lithium ion battery system according to historical fault information through an accessory fault probability model and a concurrent fault probability model of the lithium ion battery system; based on the accidental fault probability model of the lithium ion battery system, determining the accidental fault probability of the lithium ion battery system according to the battery parameters; according to the accessory fault probability, the concurrent fault probability and the accidental fault probability, calculating the comprehensive fault probability and the fault-free probability of the lithium ion battery system; and calculating the comprehensive safety entropy of the lithium ion battery system according to the comprehensive fault probability and the fault-free probability. According to the method, the concurrent faults of the system components and the accidental faults of the lithium battery body are fused, comprehensive quantitative analysis can be carried out on the concurrent faults and the accidental faults, and the fault analysis precision is improved.

Description

Technical Field

[0001] The present application belongs to the field of lithium battery management technology, and in particular, relates to a method and device for evaluating safety entropy of a lithium-ion battery system taking concurrent failures into consideration. Background Art

[0002] Lithium batteries have been widely used in automobiles, mobile phones, computers, etc. due to their high energy density, long cycle life and fast charging. However, lithium-ion battery safety accidents continue to occur, causing serious loss of life and property. Therefore, there is a huge demand for research on the safety of lithium-ion batteries.

[0003] In the qualitative assessment method, based on a decision tree, the data of the Battery Management System (BMS) is read by a small mobile device, and the battery safety status is quickly assessed based on a series of threshold judgments. Ultimately, three safety states of red, orange, and green are obtained, and the assessment results are calculated and displayed on the application.

[0004] However, lithium-ion battery system failures caused by accessory failures are called concurrent failures. The above methods for modeling concurrent failures of lithium batteries generally use methods such as fault trees and safety domain models based on Petri Net. These methods can only achieve qualitative analysis of concurrent failures, and the accuracy of fault analysis is not high. Summary of the invention

[0005] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a lithium-ion battery system safety entropy assessment method and device considering concurrent failures, which integrates concurrent failures of system components and occasional failures of the lithium battery body, and can achieve comprehensive quantitative analysis of concurrent failures and occasional failures, thereby improving the accuracy of failure analysis.

[0006] In a first aspect, the present application provides a method for evaluating safety entropy of a lithium-ion battery system considering concurrent failures, wherein the lithium-ion battery system includes a battery body and system accessories, and the method includes: Acquire historical fault information of the system accessories and battery parameters of the battery body; Determine the accessory failure probability and concurrent failure probability of the lithium-ion battery system according to the historical failure information by using an accessory failure probability model and a concurrent failure probability model of the lithium-ion battery system; Based on the accidental failure probability model of the lithium-ion battery system, determining the accidental failure probability of the lithium-ion battery system according to the battery parameters; Calculating the comprehensive failure probability and the no-failure probability of the lithium-ion battery system according to the accessory failure probability, the concurrent failure probability and the occasional failure probability; The comprehensive safety entropy of the lithium-ion battery system is calculated according to the comprehensive failure probability and the no-fault probability.

[0007] According to one embodiment of the present application, calculating the comprehensive failure probability and the no-failure probability of the lithium-ion battery system according to the concurrent failure probability and the occasional failure probability includes: Determining the probability of different types of failures of the lithium-ion battery system based on the concurrent failure probability and the accidental failure probability; The comprehensive failure probability and no-failure probability are determined according to the failure probabilities of different types.

[0008] According to one embodiment of the present application, the comprehensive failure probability is:

[0009] in, Indicated in Moment, lithium-ion battery system fails The comprehensive failure probability, , is the total number of attachments in the system attachments, It is shown that at time t due to the attachment The probability of accessory failure causing a lithium-ion battery system failure, is the probability of concurrent failures, is the probability of accidental failure at time t, is the total number of failures, yes The probability of no failure of the lithium-ion battery system at any moment; The failure-free probability of a lithium-ion battery system is:

[0010] in, is The probability of failure-free lithium-ion battery system at all times.

[0011] According to one embodiment of the present application, the comprehensive safety entropy of the lithium-ion battery system is:

[0012] in, is the comprehensive safety entropy of the lithium-ion battery system, is the total number of failures, is moment, failure of lithium-ion battery system The comprehensive failure probability, .

[0013] According to one embodiment of the present application, the sporadic failure probability model is constructed based on a BP neural network; The battery parameters include the output current, voltage, battery surface temperature and gas production pressure inside the battery pack; The probability of occasional failure includes a failure probability of an occasional failure and a probability of no failure, and the failure type of the occasional failure includes at least one of an internal short circuit failure, an overcharge failure, an over-discharge failure, a thermal runaway failure, and a gas leakage failure.

[0014] According to one embodiment of the present application, the accessory failure probability and concurrent failure probability of the lithium-ion battery system are determined according to the historical failure information through the accessory failure probability model and the concurrent failure probability model of the lithium-ion battery system, including: Inputting the historical fault information into an accessory fault probability model to obtain a fault probability of each accessory in the accessory system output by the accessory fault probability model, so as to determine the accessory fault probability of each accessory causing a fault in the lithium-ion battery system, wherein the accessory fault probability model is constructed based on a long short-term memory network; The concurrent failure probability of each accessory in the accessory system is determined based on the probability that each accessory causes the lithium-ion battery system to fail and the concurrent failure probability model.

[0015] According to one embodiment of the present application, after calculating the comprehensive safety entropy of the lithium-ion battery system, the method further includes: sending the comprehensive safety entropy to a battery control unit; The battery control unit is used to control the operating state of the lithium-ion battery system according to the comprehensive safety entropy.

[0016] In a second aspect, the present application provides a lithium-ion battery system safety entropy assessment device considering concurrent failures, wherein the lithium-ion battery system includes a battery body and system accessories, and the device includes: An acquisition module, used for acquiring historical fault information of the system accessories and battery parameters of the battery body; A first processing module, configured to determine an accessory failure probability and a concurrent failure probability of the lithium-ion battery system according to the historical failure information by using an accessory failure probability model and a concurrent failure probability model of the lithium-ion battery system; A second processing module, configured to determine the probability of accidental failure of the lithium-ion battery system according to the battery parameters based on the accidental failure probability model of the lithium-ion battery system; A third processing module, used to calculate the comprehensive failure probability and the no-failure probability of the lithium-ion battery system according to the accessory failure probability, the concurrent failure probability and the occasional failure probability; The fourth processing module is used to calculate the comprehensive safety entropy of the lithium-ion battery system according to the comprehensive failure probability and the no-fault probability.

[0017] In a third aspect, the present application provides an electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein when the processor executes the computer program, the method for evaluating safety entropy of a lithium-ion battery system taking concurrent failures into consideration as described in the first aspect above is implemented.

[0018] In a fourth aspect, the present application provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the lithium-ion battery system safety entropy assessment method considering concurrent failures as described in the first aspect above.

[0019] In a fifth aspect, the present application provides a chip, comprising a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run a program or instruction to implement the lithium-ion battery system safety entropy assessment method considering concurrent failures as described in the first aspect.

[0020] In a sixth aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the lithium-ion battery system safety entropy assessment method considering concurrent failures as described in the first aspect above.

[0021] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application.

[0022] The present application provides a method and device for evaluating safety entropy of a lithium-ion battery system taking concurrent failures into consideration, which has the following beneficial effects compared with the prior art: (1) By splitting the failures of lithium-ion battery systems into concurrent failures caused by system accessory failures and occasional failures of the battery body, the probability of concurrent failures and occasional failures are predicted separately, and the correlation between lithium-ion battery system failures is analyzed. By calculating the comprehensive safety entropy, the concurrent failures of system components and the occasional failures of the lithium battery body are integrated, which can realize a comprehensive quantitative analysis of concurrent failures and occasional failures, improve the accuracy of fault analysis, and realize real-time safety assessment of lithium-ion battery systems.

[0023] (2) Construct fault probability models for different fault categories, model concurrent fault probabilities, and use neural network algorithms to model the occasional faults of lithium batteries themselves. In the safety entropy modeling, the concurrent faults of system components and the occasional faults of the lithium battery itself are integrated. The concurrent faults caused by accessory faults and the occasional faults themselves are comprehensively considered, and the correlation between lithium-ion battery system faults is analyzed. Compared with the fault tree and safety domain models, this application considers the impact of fault uncertainty on the safety of lithium-ion batteries through comprehensive safety entropy evaluation, and realizes real-time safety entropy evaluation of lithium-ion battery systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 This is one of the flow charts of the safety entropy assessment method for a lithium-ion battery system considering concurrent failures provided in an embodiment of the present application; Figure 2 This is the second flow chart of the safety entropy assessment method for a lithium-ion battery system considering concurrent failures provided in an embodiment of the present application; Figure 3 It is a structural schematic diagram of a lithium-ion battery system safety entropy assessment device considering concurrent failures provided in an embodiment of the present application; Figure 4 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0026] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0027] In combination with the accompanying drawings, the following detailed description is made of specific embodiments and their application scenarios of the lithium-ion battery system safety entropy assessment method considering concurrent failures, the lithium-ion battery system safety entropy assessment device considering concurrent failures, the electronic device and the readable storage medium provided in the embodiments of the present application.

[0028] Among them, the lithium-ion battery system safety entropy assessment method considering concurrent failures can be applied to the terminal, and can be specifically executed by hardware or software in the terminal.

[0029] The terminal includes, but is not limited to, a portable communication device such as a mobile phone or a tablet computer having a touch-sensitive surface (e.g., a touch screen display and / or a touch pad). It should also be understood that in some embodiments, the terminal may not be a portable communication device, but a desktop computer having a touch-sensitive surface (e.g., a touch screen display and / or a touch pad).

[0030] In the following various embodiments, a terminal including a display and a touch-sensitive surface is described. However, it should be understood that the terminal may include one or more other physical user interface devices such as a physical keyboard, a mouse and a joystick.

[0031] The embodiment of the present application provides a method for evaluating the safety entropy of a lithium-ion battery system considering concurrent failures. The execution subject of the method can be an electronic device or a functional module or functional entity in the electronic device that can implement the method for evaluating the safety entropy of a lithium-ion battery system considering concurrent failures. The electronic devices mentioned in the embodiment of the present application include but are not limited to mobile phones, tablet computers, computers, cameras, and wearable devices. The method for evaluating the safety entropy of a lithium-ion battery system considering concurrent failures provided in the embodiment of the present application is described below using an electronic device as an example of the execution subject.

[0032] Wherein, the lithium-ion battery system includes a battery body and system accessories.

[0033] It should be noted that the lithium-ion battery system consists of the battery body and a variety of system accessories, including key components such as the battery management system, sensors, and connection components. These components are affected by many factors during operation, such as design defects, manufacturing process deviations, fluctuations in working conditions, and changes in the external environment. Different types of system accessory failures may occur, affecting the overall performance and safety of the lithium-ion battery system.

[0034] like Figure 1 As shown, the safety entropy assessment method of the lithium-ion battery system considering concurrent failures includes: Step 110, obtaining historical fault information of the system accessories and battery parameters of the battery body; Step 120, determining the accessory failure probability and concurrent failure probability of the lithium-ion battery system according to the historical failure information through an accessory failure probability model and a concurrent failure probability model of the lithium-ion battery system; Step 130: determining the probability of accidental failure of the lithium-ion battery system according to the battery parameters based on the accidental failure probability model of the lithium-ion battery system; Step 140, calculating the comprehensive failure probability and the no-failure probability of the lithium-ion battery system according to the accessory failure probability, the concurrent failure probability and the occasional failure probability; Step 150: Calculate the comprehensive safety entropy of the lithium-ion battery system according to the comprehensive failure probability and the no-fault probability.

[0035] It is understandable that lithium-ion battery failures can be divided into two types: the first type is caused by system accessory failures and changes in battery working conditions; the second type is accidental failures during battery operation. Therefore, the accessory failure probability model and accidental failure probability model of the battery system can be established separately.

[0036] In some embodiments, determining the accessory failure probability and concurrent failure probability of the lithium-ion battery system according to the historical failure information through an accessory failure probability model and a concurrent failure probability model of the lithium-ion battery system includes: Inputting the historical fault information into an accessory fault probability model to obtain a fault probability of each accessory in the accessory system output by the accessory fault probability model, so as to determine the accessory fault probability of each accessory causing a fault in the lithium-ion battery system, wherein the accessory fault probability model is constructed based on a long short-term memory network; The concurrent failure probability of each accessory in the accessory system is determined based on the probability that each accessory causes the lithium-ion battery system to fail and the concurrent failure probability model.

[0037] Since the failure of system accessories often has complex time-series correlation, and its failure mode and probability distribution change over time, it is crucial to accurately predict the failure of system accessories.

[0038] In terms of fault prediction, the Long Short-Term Memory (LSTM) network, with its powerful modeling capabilities for time series data, can capture the temporal correlation characteristics of fault occurrence, making it an ideal tool for processing dynamic fault analysis. The LSTM network can effectively capture the medium- and long-term dependencies of data, especially in analyzing and predicting the temporal correlation characteristics of system accessory failures. When predicting the failure probability of system accessories of a lithium-ion battery system, the occurrence probability data of the system accessories at the previous N moments can be used as input to form a time series data set. The LSTM network models the features of these input data, learns the dynamic changes of these data, and extracts the potential patterns of fault evolution, thereby more accurately predicting the probability of random failures at the tth moment.

[0039] Based on the trained accessory failure probability model, the random failure probability at time t can be output:

[0040] in, Indicates the components of the lithium-ion battery system The probability of failure at a given moment; Indicates that the system accessories are in The probability of failure occurring at any moment; Since accessory failure has a direct and significant impact on the working conditions of the lithium-ion battery system, it is reasonable to assume that accessory failure will inevitably lead to failure of the lithium-ion battery system. Therefore, in probabilistic modeling, the probability of concurrent failure of the lithium-ion battery system can be directly corresponded to the probability of accessory failure, that is:

[0041] in, Indicates that at time t, due to the system attachment The probability of accessory failure causing a lithium-ion battery system failure, Indicates the system attachment at time t i The failure probability of the lithium-ion battery system is determined by the failure type of the accessory failure.

[0042] Among them, the faults of the ion battery system may include internal short circuit fault, overcharge fault, over discharge fault, thermal runaway fault and gas leakage fault.

[0043] Internal short circuit failure is caused by damage to the internal structure of the battery, which manifests as a rapid drop in voltage and heat; overcharge failure is caused by excessive voltage during battery charging, which may lead to internal thermal runaway or decomposition reaction; over-discharge failure is caused by excessive voltage during battery discharge, which may lead to capacity decay or failure; thermal runaway failure is an uncontrollable reaction caused by a sharp increase in internal temperature, which may cause fire or explosion; gas leakage failure is caused by internal gas leakage of the battery due to abnormal pressure or damage to the outer shell. The probability of concurrent failures is shown in Table 1.

[0044] Table 1 Concurrent failure probability of lithium-ion battery system

[0045] Concurrent fault modeling is performed on the lithium-ion battery system. The number of failures of system accessories such as the battery management system / sensor / connection components in historical data is counted, and the number of internal short circuit failures / overcharge failures / overdischarge failures / thermal runaway failures / gas leakage failures caused are recorded respectively. The failure frequency is equivalent to probability to obtain a concurrent fault probability model. In the concurrent fault probability model, the concurrent fault probability Indicates that the system is attached Faults causing failures in lithium-ion battery systems The probability of .

[0046] In some embodiments, the sporadic failure probability model is constructed based on a BP neural network; The battery parameters include the output current, voltage, battery surface temperature and gas production pressure inside the battery pack; The probability of occasional failure includes a failure probability of an occasional failure and a probability of no failure, and the failure type of the occasional failure includes at least one of an internal short circuit failure, an overcharge failure, an over-discharge failure, a thermal runaway failure, and a gas leakage failure.

[0047] In order to effectively diagnose the occasional faults of lithium-ion battery systems, an occasional fault probability model based on back propagation (BP) neural network can be constructed to calculate the output current of the lithium-ion battery system. ,Voltage , Battery surface temperature And the gas pressure inside the battery pack The input feature is the probability of different faults and no faults of the lithium-ion battery system as the output.

[0048] The BP neural network includes an input layer, a hidden layer and an output layer. The number of nodes in the input layer is 4, corresponding to the four input features I, V, T, and P. In the hidden layer, the appropriate number of hidden layers and nodes are set through experimental optimization to ensure that the model has sufficient nonlinear expression capabilities. In the output layer, the number of nodes is 6, corresponding to the probabilities of no fault and five types of faults.

[0049]

[0050] in, express The probability of failure-free lithium-ion battery system at any moment, exist Time indicates occasional failures of different types of lithium-ion battery systems The probability that the output current ,Voltage , Battery surface temperature And the gas pressure inside the battery pack is the battery parameter.

[0051] The concurrent failure probability model and the accidental failure probability model of lithium-ion battery system are combined to redefine the comprehensive failure probability of lithium-ion battery system.

[0052] In some embodiments, calculating the comprehensive failure probability and the no-failure probability of the lithium-ion battery system according to the concurrent failure probability and the occasional failure probability includes: Determining the probability of different types of failures of the lithium-ion battery system based on the concurrent failure probability and the accidental failure probability; The comprehensive failure probability and no-failure probability are determined according to the failure probabilities of different types.

[0053] In some embodiments, the comprehensive failure probability is:

[0054] in, Indicated in Moment, lithium-ion battery system fails The comprehensive failure probability, , is the total number of attachments in the system attachments, It shows that at time t, due to the system accessories The probability of accessory failure causing a lithium-ion battery system failure, is the probability of concurrent failures, is the probability of accidental failure at time t, is the total number of failures, yes The probability of no failure of the lithium-ion battery system at any moment; The failure-free probability of a lithium-ion battery system is:

[0055] in, is The probability of failure-free lithium-ion battery system at all times.

[0056] After obtaining the fault types of the lithium-ion battery system and their corresponding comprehensive fault probabilities, the safety evaluation of the lithium-ion battery system can be performed based on this information. The comprehensive safety evaluation of the lithium-ion battery system depends on the probability of occurrence of various types of faults. If the probability of multiple faults is more average, it means that each fault needs to be prevented and controlled. If the probability of faults is concentrated on a certain type of fault, it means that only this type of fault needs to be prevented and controlled. Therefore, based on the information entropy theory, the concept of safety entropy is introduced to conduct a more accurate quantitative analysis of the safety status of the lithium-ion battery system.

[0057] In some embodiments, the comprehensive safety entropy of the lithium-ion battery system is:

[0058] in, is the comprehensive safety entropy of the lithium-ion battery system, is the total number of failures, is moment, failure of lithium-ion battery system The comprehensive failure probability, .

[0059] According to the safety entropy assessment method for a lithium-ion battery system taking concurrent failures into consideration provided in an embodiment of the present application, by splitting the failures of the lithium-ion battery system into concurrent failures caused by system accessory failures and occasional failures of the battery body, the probability of concurrent failures and the probability of occasional failures are predicted respectively, and the correlation between the failures of the lithium-ion battery system is analyzed. By calculating the comprehensive safety entropy, the concurrent failures of system components and the occasional failures of the lithium battery body are integrated, and a comprehensive quantitative analysis of concurrent failures and occasional failures can be achieved, thereby improving the accuracy of fault analysis and achieving real-time safety assessment of the lithium-ion battery system.

[0060] In some embodiments, after calculating the comprehensive safety entropy of the lithium-ion battery system, the method further includes: sending the comprehensive safety entropy to a battery control unit; The battery control unit is used to control the operating state of the lithium-ion battery system according to the comprehensive safety entropy.

[0061] In actual execution, the comprehensive safety entropy is sent to a battery control unit (Electric Control Unit, ECU), and the ECU controls the operating state of the lithium-ion battery system according to the comprehensive safety entropy, for example, whether to continue to operate.

[0062] The present application also provides an embodiment.

[0063] like Figure 2 As shown, on the one hand, through the accessory failure probability modeling method of the lithium-ion battery system, the LSTM neural network is used to obtain the probability model of different types of failures of the lithium-ion battery system caused by different accessory failures of the lithium-ion battery system, and the accessory failure probability model is obtained to obtain the random failure probability. , and determine the corresponding accessory failure probability based on the random failure probability .

[0064] Concurrent failure modeling is performed on the lithium-ion battery system to obtain a concurrent failure probability model and a concurrent failure probability .

[0065] On the other hand, through the accidental failure probability modeling method of lithium-ion battery system, the BP neural network is used to establish the accidental failure diagnosis model of lithium-ion battery system.

[0066] Obtaining accessory failure probability for lithium-ion battery systems , concurrent failure probability The probability of accidental failure .

[0067] By calculating the comprehensive failure probability of different failures of the lithium-ion battery system at the current operating time and the probability of no failure , according to the safety entropy model, the comprehensive safety entropy of the lithium-ion battery system at the current moment is given .

[0068] The comprehensive safety entropy of the lithium-ion battery system is transmitted to the ECU to determine whether to continue to operate. If it continues to operate, the loop is executed to obtain the accessory failure probability of the lithium-ion battery system , concurrent failure probability The probability of accidental failure , to recalculate the comprehensive security entropy , to achieve closed-loop control.

[0069] In this embodiment, fault probability models are constructed for different fault categories, Markov chains are used to model the probability of concurrent faults, and neural network algorithms are used to model the occasional faults of lithium batteries themselves. In the safety entropy modeling, the concurrent faults of system components and the occasional faults of the lithium battery body are integrated, the concurrent faults caused by accessory faults and the occasional faults themselves are comprehensively considered, and the correlation between lithium-ion battery system faults is analyzed. Compared with fault trees and safety domain models, this application takes into account the impact of fault uncertainty on the safety of lithium-ion batteries through comprehensive safety entropy evaluation, thereby realizing real-time safety entropy evaluation of lithium-ion battery systems.

[0070] The method for evaluating safety entropy of a lithium-ion battery system considering concurrent failures provided in the embodiment of the present application can be performed by a device for evaluating safety entropy of a lithium-ion battery system considering concurrent failures. In the embodiment of the present application, the device for evaluating safety entropy of a lithium-ion battery system considering concurrent failures is used as an example to illustrate the method for evaluating safety entropy of a lithium-ion battery system considering concurrent failures provided in the embodiment of the present application.

[0071] An embodiment of the present application also provides a lithium-ion battery system safety entropy assessment device that takes concurrent failures into consideration.

[0072] like Figure 3 As shown, the safety entropy assessment device for a lithium-ion battery system considering concurrent failures includes: An acquisition module 310, used to acquire historical fault information of the system accessories and battery parameters of the battery body; A first processing module 320, configured to determine the accessory failure probability and concurrent failure probability of the lithium-ion battery system according to the historical failure information by using an accessory failure probability model and a concurrent failure probability model of the lithium-ion battery system; A second processing module 330 is used to determine the accidental failure probability of the lithium-ion battery system according to the battery parameters based on the accidental failure probability model of the lithium-ion battery system; A third processing module 340 is used to calculate the comprehensive failure probability and the no-failure probability of the lithium-ion battery system according to the accessory failure probability, the concurrent failure probability and the occasional failure probability; The fourth processing module 350 is used to calculate the comprehensive safety entropy of the lithium-ion battery system according to the comprehensive failure probability and the no-fault probability.

[0073] According to the lithium-ion battery system safety entropy assessment device taking concurrent failures into consideration provided in the embodiment of the present application, by splitting the failures of the lithium-ion battery system into concurrent failures caused by system accessory failures and occasional failures of the battery body, the probability of concurrent failures and the probability of occasional failures are predicted respectively, and the correlation between the failures of the lithium-ion battery system is analyzed. By calculating the comprehensive safety entropy, the concurrent failures of system components and the occasional failures of the lithium battery body are integrated, and a comprehensive quantitative analysis of concurrent failures and occasional failures can be achieved, thereby improving the accuracy of fault analysis and realizing real-time safety assessment of the lithium-ion battery system.

[0074] The safety entropy assessment device for a lithium-ion battery system considering concurrent failures in the embodiment of the present application can be an electronic device, or a component in an electronic device, such as an integrated circuit or a chip. The electronic device can be a terminal, or it can be other devices other than a terminal. Exemplarily, the electronic device can be a mobile phone, a tablet computer, a laptop computer, a PDA, a vehicle-mounted electronic device, a mobile Internet device (Mobile Internet Device, MID), an augmented reality (AugmentedReality, AR) / virtual reality (Virtual Reality, VR) device, a robot, a wearable device, an ultra-mobile personal computer (Ultra-Mobile Personal Computer, UMPC), a netbook or a personal digital assistant (PersonalDigital Assistant, PDA), etc., and can also be a server, a network attached storage (Network AttachedStorage, NAS), a personal computer (Personal Computer, PC), a television (Television, TV), a teller machine or a self-service machine, etc., which is not specifically limited in the embodiment of the present application.

[0075] The lithium-ion battery system safety entropy assessment device considering concurrent failures in the embodiment of the present application may be a device having an operating system. The operating system may be an Android operating system, an iOS operating system, or other possible operating systems, which are not specifically limited in the embodiment of the present application.

[0076] The lithium-ion battery system safety entropy assessment device considering concurrent failures provided in the embodiment of the present application can implement the various processes implemented in the lithium-ion battery system safety entropy assessment method considering concurrent failures in the above-mentioned embodiment. To avoid repetition, they will not be repeated here.

[0077] In some embodiments, Figure 4As shown, an embodiment of the present application also provides an electronic device 400, including a processor 401, a memory 402, and a computer program stored in the memory 402 and executable on the processor 401. When the program is executed by the processor 401, each process of the embodiment of the safety entropy assessment method for a lithium-ion battery system considering concurrent failures is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be described here.

[0078] It should be noted that the electronic devices in the embodiments of the present application include the mobile electronic devices and non-mobile electronic devices mentioned above.

[0079] An embodiment of the present application also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the various processes of the above-mentioned lithium-ion battery system safety entropy assessment method embodiment considering concurrent failures are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0080] The processor is the processor in the electronic device in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0081] An embodiment of the present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the above-mentioned lithium-ion battery system safety entropy assessment method considering concurrent failures.

[0082] The processor is the processor in the electronic device in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.

[0083] An embodiment of the present application further provides a chip, which includes a processor and a communication interface, wherein the communication interface and the processor are coupled, and the processor is used to run programs or instructions to implement the various processes of the above-mentioned embodiment of the lithium-ion battery system safety entropy assessment method considering concurrent failures, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0084] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0085] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0086] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment method can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, disk, CD), including a number of instructions for a terminal (which can be a mobile phone, computer, server, or network equipment, etc.) to execute the lithium-ion battery system safety entropy assessment method considering concurrent failures in each embodiment of the present application.

[0087] In the description of this application, "first feature" or "second feature" may include one or more of the features.

[0088] In the description of the present application, “plurality” means two or more.

[0089] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

[0090] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0091] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A safety entropy assessment method for a lithium-ion battery system considering concurrent failures, characterized in that: The lithium-ion battery system includes a battery body and system accessories, and the method includes: Acquire historical fault information of the system accessories and battery parameters of the battery body; Determine the accessory failure probability and concurrent failure probability of the lithium-ion battery system according to the historical failure information by using an accessory failure probability model and a concurrent failure probability model of the lithium-ion battery system; Based on the accidental failure probability model of the lithium-ion battery system, determining the accidental failure probability of the lithium-ion battery system according to the battery parameters; Calculating the comprehensive failure probability and the no-failure probability of the lithium-ion battery system according to the accessory failure probability, the concurrent failure probability and the occasional failure probability; The comprehensive safety entropy of the lithium-ion battery system is calculated according to the comprehensive failure probability and the no-fault probability.

2. The method for evaluating safety entropy of a lithium-ion battery system considering concurrent failures according to claim 1 is characterized in that: Calculating the comprehensive failure probability and the no-failure probability of the lithium-ion battery system according to the concurrent failure probability and the occasional failure probability includes: Determining the probability of different types of failures of the lithium-ion battery system based on the concurrent failure probability and the accidental failure probability; The comprehensive failure probability and no-failure probability are determined according to the failure probabilities of different types.

3. The method for evaluating safety entropy of a lithium-ion battery system considering concurrent failures according to claim 2, characterized in that: The comprehensive failure probability is: ； in, Indicated in Moment, lithium-ion battery system fails The comprehensive failure probability, , is the total number of attachments in the system attachments, It is shown that at time t due to the attachment The probability of accessory failure causing a lithium-ion battery system failure, is the probability of concurrent failures, is the probability of accidental failure at time t, is the total number of failures, yes The probability of failure-free lithium-ion battery system at all times; The failure-free probability of a lithium-ion battery system is: ； in, is The probability of failure-free lithium-ion battery system at all times.

4. The method for evaluating safety entropy of a lithium-ion battery system considering concurrent failures according to claim 1, characterized in that: The comprehensive safety entropy of the lithium-ion battery system is: ； in, is the comprehensive safety entropy of the lithium-ion battery system, is the total number of failures, is moment, failure of lithium-ion battery system The comprehensive failure probability, .

5. The method for evaluating safety entropy of a lithium-ion battery system considering concurrent failures according to claim 1, characterized in that: The sporadic failure probability model is constructed based on BP neural network; The battery parameters include the output current, voltage, battery surface temperature and gas production pressure inside the battery pack; The probability of occasional failure includes the probability of failure of occasional failure and the probability of no failure, and the failure type of the occasional failure includes at least one of an internal short circuit failure, an overcharge failure, an over-discharge failure, a thermal runaway failure and a gas leakage failure.

6. The method for evaluating safety entropy of a lithium-ion battery system considering concurrent failures according to claim 1, characterized in that: Determining the accessory failure probability and concurrent failure probability of the lithium-ion battery system according to the historical failure information through an accessory failure probability model and a concurrent failure probability model of the lithium-ion battery system, including: Inputting the historical fault information into an accessory fault probability model to obtain a fault probability of each accessory in the accessory system output by the accessory fault probability model, so as to determine the accessory fault probability of each accessory causing a fault in the lithium-ion battery system, wherein the accessory fault probability model is constructed based on a long short-term memory network; The concurrent failure probability of each accessory in the accessory system is determined based on the probability that each accessory causes the lithium-ion battery system to fail and the concurrent failure probability model.

7. The method for evaluating safety entropy of a lithium-ion battery system considering concurrent failures according to claim 1, characterized in that: After calculating the comprehensive safety entropy of the lithium-ion battery system, the method further includes: sending the comprehensive safety entropy to a battery control unit; The battery control unit is used to control the operating state of the lithium-ion battery system according to the comprehensive safety entropy.

8. A lithium-ion battery system safety entropy assessment device considering concurrent failures, characterized in that: The lithium-ion battery system includes a battery body and system accessories, and the device includes: An acquisition module, used for acquiring historical fault information of the system accessories and battery parameters of the battery body; A first processing module, configured to determine an accessory failure probability and a concurrent failure probability of the lithium-ion battery system according to the historical failure information by using an accessory failure probability model and a concurrent failure probability model of the lithium-ion battery system; A second processing module, configured to determine the probability of accidental failure of the lithium-ion battery system according to the battery parameters based on the accidental failure probability model of the lithium-ion battery system; A third processing module, used to calculate the comprehensive failure probability and the no-failure probability of the lithium-ion battery system according to the accessory failure probability, the concurrent failure probability and the occasional failure probability; The fourth processing module is used to calculate the comprehensive safety entropy of the lithium-ion battery system according to the comprehensive failure probability and the no-fault probability.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method for evaluating safety entropy of a lithium-ion battery system taking concurrent failures into consideration is implemented as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for evaluating safety entropy of a lithium-ion battery system taking concurrent failures into consideration as described in any one of claims 1 to 7 is implemented.

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