Method and device for early warning of internal short circuit of lithium iron phosphate battery of vehicle

Abstract

The application relates to the technical field of battery management, in particular to a method and device for early warning of internal short circuit of a lithium iron phosphate battery of a vehicle, wherein the method comprises the following steps: acquiring charging battery data of the lithium iron phosphate battery of the vehicle; acquiring a battery voltage curve of the lithium iron phosphate battery according to the charging battery data, and obtaining a plurality of feature points according to a plurality of curvature maximum points of the battery voltage curve; acquiring change information between the plurality of feature points, and controlling the vehicle to give a warning prompt when the change information reaches a preset internal short circuit early warning condition. According to the application, the plurality of feature points can be obtained according to the plurality of curvature maximum points of the battery voltage curve of the lithium iron phosphate battery, and the vehicle can be controlled to give a warning prompt when the change information between the plurality of feature points reaches the preset internal short circuit early warning condition, so that the accuracy of the calculation result is effectively improved, and the robustness and real-time performance of the internal short circuit early warning of the battery are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery management, and in particular relates to a method and device for early warning of internal short circuit of a lithium iron phosphate battery of a vehicle. BACKGROUND

[0002] With the rapid increase in the number of electric vehicles, the overheat events of electric vehicles have also attracted the attention of consumers. Thermal runaway of power batteries can pose a threat to property safety and personal safety. One of the main reasons for thermal runaway is internal short circuit of the battery.

[0003] In related technologies, the internal short circuit of the battery is calculated by full charging of the power battery or reaching a reference voltage, and a warning is given. For example, in patent CN107870301A, the first reference charging capacity at the first charging end time and the second reference charging capacity at the second charging end time of the to-be-tested single battery included in the to-be-tested battery pack are obtained, and the difference between the first reference charging capacity and the second reference charging capacity is used to determine that the to-be-tested single battery has a micro-short circuit, so as to detect thermal runaway of the power battery.

[0004] However, in related technologies, due to the voltage platform of the lithium iron phosphate battery, the internal short circuit of the battery is calculated by calculating the short circuit internal resistance of the power battery, which results in a large deviation in the calculation result, reduces the robustness and real-time performance of the battery internal short circuit early warning, and needs to be solved urgently. SUMMARY

[0005] The present application is based on the following problems and realizations of the inventors:

[0006] Lithium ion batteries are favored by electric vehicles and even energy storage devices due to their long cycle life, high energy density, and other advantages. In recent years, due to the development of structural innovation technology, the cost and safety of lithium iron phosphate batteries have gradually increased, and the number of vehicles equipped with lithium iron phosphate batteries has also gradually increased. With the rapid increase in the number of electric vehicles, the overheat events of electric vehicles have also attracted the attention of consumers. Thermal runaway of power batteries can pose a threat to property safety and personal safety.

[0007] One of the main reasons for thermal runaway is internal short circuit of the battery. Dust, raw material burrs, or foreign matter during production can cause internal short circuit of the battery, consume the battery capacity, increase the inconsistency of the battery pack, and thus affect the performance of the power battery. As the internal short circuit worsens, the self-discharge rate increases, causing an increase in heat production, and even the risk of thermal runaway. Therefore, early warning of internal short circuit of the power battery and timely disposal can reduce the occurrence of safety incidents.

[0008] Because the voltage curve plateau of ternary lithium batteries is not obvious, while lithium iron phosphate batteries have two plateau periods, current internal short circuit warning methods are mostly applicable to ternary lithium batteries. They often use calculation of short circuit internal resistance for warning, which often requires full charging or reaching a reference voltage. Due to the voltage plateau of lithium iron phosphate batteries, traditional warning calculation methods often have large deviations, resulting in inaccurate results.

[0009] This application provides a method and apparatus for early warning of internal short circuits in lithium iron phosphate batteries for vehicles, in order to solve the problems in related technologies where, due to the voltage plateau of lithium iron phosphate batteries, early warning is based on the calculation of the short-circuit internal resistance of the power battery, resulting in large deviations in the calculation results and reducing the robustness and real-time performance of the battery short-circuit warning.

[0010] The first aspect of this application provides a method for early warning of internal short circuit in a vehicle's lithium iron phosphate battery, comprising the following steps: acquiring rechargeable battery data of the vehicle's lithium iron phosphate battery; acquiring the battery voltage curve of the lithium iron phosphate battery based on the rechargeable battery data, and obtaining multiple feature points based on multiple curvature maxima of the battery voltage curve; acquiring change information between the multiple feature points, and controlling the vehicle to issue an early warning when the change information reaches a preset internal short circuit warning condition.

[0011] Based on the above technical means, the embodiments of this application can obtain multiple feature points based on multiple curvature maxima of the battery voltage curve of lithium iron phosphate battery, and when the change information between multiple feature points reaches the preset internal short circuit warning condition, control the vehicle to issue a warning, effectively improving the accuracy of the calculation results and enhancing the robustness and real-time performance of the battery internal short circuit warning.

[0012] Optionally, in one embodiment of this application, the step of obtaining the battery voltage curve of the lithium iron phosphate battery based on the rechargeable battery data, and obtaining multiple feature points based on multiple curvature maxima of the battery voltage curve, includes: obtaining the voltage-charge capacity curve of each individual cell of the lithium iron phosphate battery; calculating the radius of curvature-charge capacity curve of the voltage-charge capacity curve; and obtaining multiple feature points of each individual cell based on the radius of curvature-charge capacity curve.

[0013] Based on the above technical means, the embodiments of this application can calculate the voltage curvature radius curve based on the voltage curve of each individual cell of the lithium iron phosphate battery, thereby obtaining multiple feature points of each individual cell, effectively improving the real-time performance of short circuit warning in the battery.

[0014] Optionally, in an embodiment of the present application, the obtaining the change information between the plurality of feature points comprises: calculating a target capacity difference value of the plurality of feature points of each single battery and the plurality of feature points of a reference single battery respectively; and calculating a change rate of the target capacity difference value based on a change relationship of the target capacity difference value over time to obtain the change information.

[0015] According to the above technical means, the embodiment of the present application can judge whether the vehicle needs to be controlled for pre-warning by calculating the change rate of the target capacity difference value, effectively improving the robustness of the battery internal short circuit pre-warning and improving the safety and reliability of the vehicle.

[0016] Optionally, in an embodiment of the present application, the controlling the vehicle for pre-warning when the change information reaches the preset internal short circuit pre-warning condition comprises: judging whether the change rate is greater than a preset threshold; and if the change rate is greater than the preset threshold, determining that the preset internal short circuit pre-warning condition is reached.

[0017] According to the above technical means, the embodiment of the present application can determine that the internal short circuit pre-warning condition is reached when the change rate is greater than a certain threshold, thereby improving the robustness of the battery internal short circuit pre-warning.

[0018] Optionally, in an embodiment of the present application, before the target capacity difference value is calculated, the method further comprises: taking a single battery that is first fully charged in a first charging segment of the lithium iron phosphate battery as the reference single battery.

[0019] According to the above technical means, the embodiment of the present application can determine the reference single battery and can select a plurality of reference single batteries, thereby effectively improving the accuracy of the target capacity difference value.

[0020] The second aspect embodiment of the present application provides a device for internal short circuit pre-warning of a lithium iron phosphate battery of a vehicle, comprising: a first obtaining module configured to obtain charging battery data of a lithium iron phosphate battery of a vehicle; a second obtaining module configured to obtain a battery voltage curve of the lithium iron phosphate battery according to the charging battery data, and obtain a plurality of feature points according to a plurality of curvature maximum points of the battery voltage curve; and a control module configured to obtain change information between the plurality of feature points, and control the vehicle for pre-warning when the change information reaches a preset internal short circuit pre-warning condition.

[0021] Optionally, in an embodiment of the present application, the second obtaining module comprises: a first obtaining unit configured to obtain a voltage-charged capacity curve of each single battery of the lithium iron phosphate battery; a calculation unit configured to calculate a curvature radius-charged capacity curve of the voltage-charged capacity curve; and a second obtaining unit configured to obtain a plurality of feature points of each single battery according to the curvature radius-charged capacity curve.

[0022] Optionally, in an embodiment of the present application, the obtaining the change information between the plurality of feature points comprises: calculating a target capacity difference value of the plurality of feature points of each single battery and the plurality of feature points of the reference single battery respectively, calculating a change rate of the target capacity difference value based on a change relationship of the target capacity difference value over time, and obtaining the change information.

[0023] Optionally, in an embodiment of the present application, the control module comprises: a judgment unit configured to judge whether the change rate is greater than a preset threshold; and a processing unit configured to determine that the preset internal short circuit early warning condition is reached if the change rate is greater than the preset threshold.

[0024] Optionally, in an embodiment of the present application, the device of the embodiment of the present application further comprises: a determination module configured to determine a single battery in which a first charging segment is first fully charged as the reference single battery before the target capacity difference value is calculated.

[0025] The third aspect of the embodiment of the present application provides a vehicle, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor executes the program to implement the method for early warning of an internal short circuit of a lithium iron phosphate battery of the vehicle as described in the above embodiments.

[0026] The fourth aspect of the embodiment of the present application provides a computer readable storage medium, which stores a computer program, and the program is executed by a processor to implement the method for early warning of an internal short circuit of a lithium iron phosphate battery of a vehicle as described above.

[0027] The beneficial effects of the present application are as follows:

[0028] (1) The embodiment of the present application can calculate a voltage curvature radius curve according to a voltage curve of each single battery of a lithium iron phosphate battery, thereby obtaining a plurality of feature points of each single battery, and effectively improving the real-time performance of the early warning of the internal short circuit of the battery.

[0029] (2) The embodiment of the present application can judge whether the vehicle needs to be controlled for early warning prompt by calculating the change rate of the target capacity difference value, effectively improving the robustness of the early warning of the internal short circuit of the battery, and improving the safety and reliability of the vehicle.

[0030] (3) The embodiment of the present application can obtain a plurality of feature points according to a plurality of curvature maximum points of a battery voltage curve of a lithium iron phosphate battery, and control the vehicle for early warning prompt when the change information between the plurality of feature points reaches a preset internal short circuit early warning condition, effectively improving the accuracy of the calculation result, and improving the robustness and real-time performance of the early warning of the internal short circuit of the battery.

[0031] Additional aspects and advantages of the present application will be made apparent from the following description with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0032] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, with reference to the following figures, wherein:

[0033] Figure 1 A flow chart of a method for early warning of internal short circuit of a lithium iron phosphate battery of a vehicle according to an embodiment of the present application;

[0034] Figure 2 A voltage curve diagram of a lithium iron phosphate battery according to an embodiment of the present application;

[0035] Figure 3 A curvature curve and feature point diagram of a lithium iron phosphate battery according to an embodiment of the present application;

[0036] Figure 4 A single cell voltage change diagram of internal short circuit of a lithium iron phosphate battery according to an embodiment of the present application;

[0037] Figure 5 A first capacity difference change trend diagram of internal short circuit of a lithium iron phosphate battery according to an embodiment of the present application;

[0038] Figure 6 A structure diagram of a device for early warning of internal short circuit of a lithium iron phosphate battery of a vehicle according to an embodiment of the present application;

[0039] Figure 7 A structure diagram of a vehicle according to an embodiment of the present application. DETAILED DESCRIPTION

[0040] Embodiments of the present application are described in detail below with reference to the accompanying drawings, examples of which are shown in the drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application.

[0041] A method and device for early warning of internal short circuit of a lithium iron phosphate battery of a vehicle are described below with reference to the accompanying drawings. In view of the problems in the prior art that the early warning of internal short circuit of a lithium iron phosphate battery of a vehicle is not robust and real-time due to the voltage platform of the lithium iron phosphate battery, the present application provides a method for early warning of internal short circuit of a lithium iron phosphate battery of a vehicle. In the method, a battery voltage curve of the lithium iron phosphate battery can be obtained according to charging battery data of the lithium iron phosphate battery of the vehicle, and a plurality of feature points can be obtained according to a plurality of curvature maximum points of the battery voltage curve. When the change information between the plurality of feature points reaches a preset internal short circuit early warning condition, the vehicle is controlled to give a warning prompt, thereby effectively improving the accuracy of the calculation result and improving the robustness and real-time performance of the early warning. Thus, the problems in the prior art that the early warning of internal short circuit of a lithium iron phosphate battery of a vehicle is not robust and real-time due to the voltage platform of the lithium iron phosphate battery are solved.

[0042] Specifically, Figure 1 A flowchart of a method for early warning of internal short circuit of a lithium iron phosphate battery of a vehicle is provided in the present application.

[0043] As Figure 1 shown, the method for early warning of internal short circuit of a lithium iron phosphate battery of a vehicle includes the following steps:

[0044] In step S101, charging battery data of a lithium iron phosphate battery of a vehicle is obtained.

[0045] It can be understood that the charging battery data of the lithium iron phosphate battery of the vehicle can be obtained, for example, the charging time, the voltage and the current of each single battery, etc. of the battery can be obtained, thereby effectively improving the executability of the early warning of internal short circuit of the battery.

[0046] For example, the extracted fields can be data cleaned to remove invalid data, and the charging data can be divided. Each continuous charging period can be regarded as a charging segment, a total of m charging segments, and the charging segments can be sorted by time, and the serial numbers are sequentially marked as 1, 2, …, m.

[0047] Secondly, the cumulative charging capacity at different time points in different charging periods can be calculated. The capacity can be calculated by using the ampere-hour integration method, and the integral method of discrete data is used. The charging data has n rows in total. The charging time is denoted as t1, t2, …, t n , the current is denoted as I1, I2, …, I n , and the capacity is denoted as Q1, Q2, …, Q

[0048] Qm =(Q1 m , Q2 m ..., Q n m )

[0049]

[0050] where Q m represents the charging capacity vector of the m-th charging segment, and Q p m represents the cumulative charging capacity at the p-th moment of the m-th charging segment.

[0051] In step S102, according to the charging battery data, the battery voltage curve of the lithium iron phosphate battery is obtained, and multiple characteristic points are obtained based on multiple curvature maximum points of the battery voltage curve.

[0052] It can be understood that in the embodiments of the present application, the battery voltage curve of the lithium iron phosphate battery can be obtained according to the charging battery data in the following steps, and multiple characteristic points are obtained based on multiple curvature maximum points of the battery voltage curve, effectively improving the real-time performance of the in-battery short circuit warning.

[0053] Among them, in an embodiment of the present application, obtaining the battery voltage curve of the lithium iron phosphate battery according to the charging battery data and obtaining multiple characteristic points based on multiple curvature maximum points of the battery voltage curve includes: obtaining the voltage-charging capacity curve of each single battery of the lithium iron phosphate battery; calculating the curvature radius-charging capacity curve of the voltage-charging capacity curve; and obtaining multiple characteristic points of each single battery according to the curvature radius-charging capacity curve.

[0054] For example, as Figure 2 shown, in the embodiments of the present application, the voltage-charging capacity curve of each single battery of the lithium iron phosphate battery can be obtained, the voltage-charging capacity curve of each single battery is filtered, and the charging capacity is interpolated. Let x be the equally spaced charging power, the minimum value is 0, the maximum value is the maximum value max(Q) of the current charging power, the spacing is assumed to be 0.1, f(x) is the value obtained by interpolating the U-Q curve according to the x value, or the voltage-charging capacity curve is function-fitted. Among them, the interpolation formula is:

[0055]

[0056] where Q1 and Q2 represent two charging power points on both sides of x, Q1 < x < Q2, and U1 and U2 respectively represent the voltage values corresponding to the charging powers Q1 and Q2.

[0057] Next, in the embodiments of the present application, the curvature radius can be solved. Among them, the curvature radius solving formula is:

[0058]

[0059] wherein, δ represents the interval of x, such as 0.1 Ah.

[0060] Secondly, after fitting the voltage-charge capacity curve, the curvature radius r is calculated by using the function derivative curvature, and the curvature K is the inverse of the curvature radius r, that is:

[0061]

[0062] For example, as shown in the following formula, the voltage-charge capacity curve is solved, and the maximum point of the curvature K is solved before and after the two platforms of the voltage, and the charge capacity value corresponding to the maximum point is recorded as the first characteristic point X1, the second characteristic point X2 and the third characteristic point X3, wherein the curvature K of the voltage-charge capacity curve is: Figure 3

[0063]

[0064] In summary, the embodiments of the present application can obtain a plurality of characteristic points according to the battery voltage curve of the lithium iron phosphate battery and according to a plurality of curvature maximum points of the battery voltage curve, thereby effectively improving the real-time performance of the battery internal short circuit early warning.

[0065] In step S103, the change information between the plurality of characteristic points is obtained, and when the change information reaches the preset internal short circuit early warning condition, the vehicle is controlled to perform early warning prompt.

[0066] It can be understood that the embodiments of the present application can obtain the change information between the plurality of characteristic points in the following steps, and when the change information in the following steps reaches the preset internal short circuit early warning condition, the vehicle is controlled to perform early warning prompt, thereby effectively improving the robustness of the battery internal short circuit early warning and improving the safety and reliability of the vehicle.

[0067] Optionally, in an embodiment of the present application, the change information between the plurality of characteristic points is obtained, including: calculating the target capacity difference between the plurality of characteristic points of each single battery and the plurality of characteristic points of the reference single battery, respectively; calculating the change rate of the target capacity difference based on the change relationship of the target capacity difference with time to obtain the change information.

[0068] For example, the embodiments of the present application can calculate the difference between the first characteristic point, the second characteristic point and the third characteristic point of each single battery and the first characteristic point, the second characteristic point and the third characteristic point of the reference single battery, respectively, which are denoted as the first capacity difference ΔQ1, the second capacity difference ΔQ2 and the third capacity difference ΔQ3, and can be represented as:

[0069] ​

[0070]

[0071]

[0072] wherein, represents the first feature point of the monomer i in the mth charging, r represents a reference monomer, and the reference monomer is selected and does not change, λ T represents a temperature correction coefficient, that is, the deviation of the battery charging capacity at different charging temperatures from the charging capacity at 25℃.

[0073] In addition, the embodiment of the present application can calculate the change trend of the first capacity difference, the second capacity difference and the third capacity difference of each monomer. Taking the first capacity difference as an example, the second capacity difference and the third capacity difference are the same. The specific calculation process is as follows:

[0074]

[0075] wherein, represents the first capacity difference change trend calculated at the m+αth charging time of the monomer i, and a represents a sliding window length, which is an integer greater than or equal to 2.

[0076] In summary, the embodiment of the present application can determine whether the vehicle needs to be controlled for pre-warning by calculating the change rate of the target capacity difference value, effectively improving the robustness of the battery internal short circuit pre-warning and improving the safety and reliability of the vehicle.

[0077] Optionally, in an embodiment of the present application, when the change information reaches the preset internal short circuit pre-warning condition, the vehicle is controlled for pre-warning, including: determining whether the change rate is greater than a preset threshold; if it is greater than the preset threshold, it is determined that the preset internal short circuit pre-warning condition is reached.

[0078] For example, as shown in FIGS. 1 and 2, the voltage curve change of the monomer with an internal short circuit risk and the change trend of the first capacity difference of the monomer are shown. Figure 4 and Figure 5 The embodiment of the present application can determine whether the change trend of the first capacity difference in the above steps exceeds the threshold value. When it exceeds the threshold value, the internal short circuit pre-warning is triggered, and the vehicle can be further limited, and the vehicle can be repaired or replaced in time, effectively improving the safety and reliability of the vehicle.

[0079] In an embodiment of the present application, before calculating the target capacity difference value, it further includes: taking the monomer battery that is first fully charged in the first charging segment of the lithium iron phosphate battery as the reference monomer battery.

[0080] As a possible implementation manner, the embodiment of the present application can take the first full charging monomer of the lithium iron phosphate battery as the reference monomer, and can select several reference monomers, thereby effectively improving the accuracy of the target capacity difference.

[0081] According to the method for early warning of internal short circuit of the lithium iron phosphate battery of the vehicle provided in the embodiment of the present application, the battery voltage curve of the lithium iron phosphate battery can be obtained according to the charging battery data of the lithium iron phosphate battery of the vehicle, a plurality of feature points can be obtained according to a plurality of curvature maximum points of the battery voltage curve, and the vehicle is controlled to perform early warning prompt when the change information between the plurality of feature points reaches a preset internal short circuit early warning condition, thereby effectively improving the accuracy of the calculation result, and improving the robustness and real-time performance of the early warning. Thus, the problems in the related art that the calculation result has a large deviation due to the voltage platform of the lithium iron phosphate battery, the internal short circuit of the power battery is calculated to perform early warning, and the robustness and real-time performance of the early warning of the battery internal short circuit are reduced are solved.

[0082] Secondly, the device for early warning of internal short circuit of the lithium iron phosphate battery of the vehicle according to the embodiment of the present application is described with reference to the accompanying drawings.

[0083] Figure 6 is a block schematic diagram of the device for early warning of internal short circuit of the lithium iron phosphate battery of the vehicle according to the embodiment of the present application.

[0084] As Figure 6 shown, the device 10 for early warning of internal short circuit of the lithium iron phosphate battery of the vehicle includes a first obtaining module 100, a second obtaining module 200 and a control module 300.

[0085] Specifically, the first obtaining module 100 is configured to obtain charging battery data of the lithium iron phosphate battery of the vehicle.

[0086] The second obtaining module 200 is configured to obtain a battery voltage curve of the lithium iron phosphate battery according to the charging battery data, and obtain a plurality of feature points according to a plurality of curvature maximum points of the battery voltage curve.

[0087] The control module 300 is configured to obtain change information between the plurality of feature points, and control the vehicle to perform early warning prompt when the change information reaches a preset internal short circuit early warning condition.

[0088] Optionally, in an embodiment of the present application, the second obtaining module 200 includes a first obtaining unit, a calculation unit and a second obtaining unit.

[0089] The first obtaining unit is configured to obtain a voltage-charged capacity curve of each monomer battery of the lithium iron phosphate battery.

[0090] The calculation unit is configured to calculate a curvature radius-charged capacity curve of the voltage-charged capacity curve.

[0091] The second acquisition unit is configured to acquire the plurality of feature points of each single battery according to the curvature radius-charge capacity curve.

[0092] Optionally, in an embodiment of the present application, the acquiring the change information between the plurality of feature points comprises: calculating a target capacity difference value between the plurality of feature points of each single battery and the plurality of feature points of the reference single battery respectively, calculating a change rate of the target capacity difference value based on a change relationship of the target capacity difference value over time, and obtaining the change information.

[0093] Optionally, in an embodiment of the present application, the control module 300 comprises a judgment unit and a processing unit.

[0094] The judgment unit is configured to judge whether the change rate is greater than a preset threshold.

[0095] The processing unit is configured to determine that a preset internal short circuit early warning condition is reached if the change rate is greater than the preset threshold.

[0096] Optionally, in an embodiment of the present application, the device 10 of the embodiment of the present application further comprises a determination module.

[0097] The determination module is configured to take the single battery in the lithium iron phosphate battery which is first fully charged in a first charging segment as the reference single battery before calculating the target capacity difference value.

[0098] It should be noted that the foregoing explanation and description of the method embodiment for early warning of internal short circuit of the lithium iron phosphate battery of the vehicle also applies to the device for early warning of internal short circuit of the lithium iron phosphate battery of the vehicle of this embodiment, which will not be described here again.

[0099] The device for early warning of internal short circuit of the lithium iron phosphate battery of the vehicle according to the embodiment of the present application can acquire a battery voltage curve of the lithium iron phosphate battery according to the charging battery data of the lithium iron phosphate battery of the vehicle, and obtain a plurality of feature points according to a plurality of curvature maximum points of the battery voltage curve. When the change information between the plurality of feature points reaches a preset internal short circuit early warning condition, the vehicle is controlled to perform early warning prompt, which effectively improves the accuracy of the calculation result and improves the robustness and real-time performance of the early warning. Thus, the problem that the calculation result has a large deviation due to the voltage platform of the lithium iron phosphate battery, the early warning is performed by calculating the internal short circuit resistance of the power battery in the related art, and the robustness and real-time performance of the early warning of the battery internal short circuit are reduced is solved.

[0100] Figure 7 A structural schematic diagram of a vehicle is provided for the embodiment of the present application. The vehicle can comprise:

[0101] The memory 701, the processor 702, and the computer program stored in the memory 701 and executable on the processor 702.

[0102] The processor 702 implements the method for early warning of the short circuit in the lithium-iron-phosphate battery of the vehicle provided in the above embodiments when executing a program.

[0103] Further, the vehicle further comprises:

[0104] The communication interface 703 is configured to communicate between the memory 701 and the processor 702.

[0105] The memory 701 is configured to store a computer program executable in the processor 702.

[0106] The memory 701 can include a high-speed RAM memory, and can further include a non-volatile memory, for example, at least one disk memory.

[0107] If the memory 701, the processor 702 and the communication interface 703 are implemented independently, the communication interface 703, the memory 701 and the processor 702 can be connected to each other through a bus and complete the communication between each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, Figure 7 Only one thick line is used in the figure, but it does not mean that there is only one bus or only one type of bus.

[0108] Optionally, in a specific implementation, if the memory 701, the processor 702 and the communication interface 703 are integrated on a chip, the memory 701, the processor 702 and the communication interface 703 can complete the communication between each other through an internal interface.

[0109] The processor 702 can be a Central Processing Unit (CPU), or an Application Specific Integrated Circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0110] The embodiments of the present application further provide a computer readable storage medium, which has stored a computer program, and the program is executed by the processor to implement the method for early warning of the short circuit in the lithium-iron-phosphate battery of the vehicle as above.

[0111] In the description of the application, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the application. The illustrative description of the above terms in the specification does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in one or N embodiments or examples. In addition, the skilled person can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples, without contradiction.

[0112] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the application, the meaning of "N" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0113] Any process or method descriptions in flow charts or otherwise described herein represent embodiments that can be understood as a set of steps, operations, or stages of implementing the functionality described, and that such a set of steps, operations, or stages can be performed in the order described, in a different order than described, or concurrently. One or more steps, operations, or stages can be omitted, repeated, or combined with other steps, operations, or stages that are described, in accordance with the principles of the application.

[0114] The logic and / or steps represented in the flowcharts and / or described herein, for example, can be considered as a sequence of instructions to implement logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, apparatus, or device, such as a computer-based system, processor- based system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For purposes of this specification, a "computer-readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer-readable medium can be a computer- readable storage medium or a computer-readable signal medium. The computer- readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer-readable storage medium include the following: an electrical connection having one or more wires (electrical connections), a portable computer diskette (a magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium can even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via, for example, optical scanning of the paper or other medium, then compiled, interpreted, or otherwise processed in a suitable manner, if necessary, and then stored in a computer memory.

[0115] It should be understood that aspects of the application can be implemented in hardware, software, firmware or combinations thereof. In the above embodiments, the N steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented in hardware and in another embodiment, any of the following technologies, known in the art, or their combinations can be used: discrete logic circuitry having logic gates for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gates, programmable gate arrays (PGA), field programmable gate arrays (FPGA), etc.

[0116] Those skilled in the art can understand that all or part of the steps carried out by the above-mentioned embodiments can be completed by programs instructing related hardware, and the programs can be stored in a computer-readable storage medium. When the programs are executed, one or a combination of the steps of the method embodiments is included.

[0117] In addition, each of the functional units in the various embodiments of the present application can be integrated in one processing module, or each of the units can be physically present separately, or two or more units can be integrated in one module. The integrated module can be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer readable storage medium.

[0118] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A method for early warning of internal short circuit of a lithium-iron-phosphate battery of a vehicle, characterized in that, The method comprises the following steps: obtaining charging battery data of a lithium-iron-phosphate battery of a vehicle; obtaining a battery voltage curve of the lithium-iron-phosphate battery according to the charging battery data, and obtaining a plurality of feature points according to a plurality of curvature maximum points of the battery voltage curve; and obtaining change information between the plurality of feature points, and controlling the vehicle to give a warning prompt when the change information reaches a preset internal short-circuit warning condition; the step of obtaining the battery voltage curve of the lithium-iron-phosphate battery according to the charging battery data, and obtaining a plurality of feature points according to a plurality of curvature maximum points of the battery voltage curve comprises: obtaining a voltage-charging capacity curve of each single battery of the lithium-iron-phosphate battery; calculating a curvature radius-charging capacity curve of the voltage-charging capacity curve; obtaining a plurality of feature points of each single battery according to the curvature radius-charging capacity curve.

2. The method of claim 1, wherein, the step of obtaining change information between the plurality of feature points comprises: respectively calculating a target capacity difference value of the plurality of feature points of each single battery and the plurality of feature points of a reference single battery; calculating a change rate of the target capacity difference value based on a transformation relationship of the target capacity difference value over time to obtain the change information.

3. The method of claim 2, wherein, the step of controlling the vehicle to give a warning prompt when the change information reaches a preset internal short-circuit warning condition comprises: determining whether the change rate is greater than a preset threshold value; if the change rate is greater than the preset threshold value, it is determined that the preset internal short-circuit warning condition is reached.

4. The method of claim 2, wherein, Before calculating the target capacity difference value, the method further comprises: taking a single battery that is first fully charged in a first charging segment of the lithium-iron-phosphate battery as the reference single battery.

5. A device for early warning of internal short circuit of a lithium-iron-phosphate battery of a vehicle, characterized in that, The method comprises: a first obtaining module for obtaining charging battery data of a lithium-iron-phosphate battery of a vehicle; a second obtaining module for obtaining a battery voltage curve of the lithium-iron-phosphate battery according to the charging battery data, and obtaining a plurality of feature points according to a plurality of curvature maximum points of the battery voltage curve; and a control module for obtaining change information between the plurality of feature points, and controlling the vehicle to give a warning prompt when the change information reaches a preset internal short-circuit warning condition; the second obtaining module comprises: a first obtaining unit for obtaining a voltage-charging capacity curve of each single battery of the lithium-iron-phosphate battery; a calculation unit for calculating a curvature radius-charging capacity curve of the voltage-charging capacity curve; a second obtaining unit for obtaining a plurality of feature points of each single battery according to the curvature radius-charging capacity curve.

6. The apparatus of claim 5, wherein, the step of obtaining change information between the plurality of feature points comprises respectively calculating a target capacity difference value of the plurality of feature points of each single battery and the plurality of feature points of a reference single battery, and calculating a change rate of the target capacity difference value based on a transformation relationship of the target capacity difference value over time to obtain the change information.

7. A vehicle characterized by comprising: The method comprises: a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to implement the method for internal short-circuit warning of a lithium-iron-phosphate battery of a vehicle according to any one of claims 1-4.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor for implementing the method for early warning of short circuit in the lithium-iron-phosphate battery of the vehicle according to any one of claims 1-4.

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