A method, system, device and medium for locating and identifying abnormal cells in a battery pack

Abstract

The present invention discloses a method, system, device and medium for locating and identifying abnormal cells in a battery pack, and specifically relates to the field of battery technology. The method comprises: obtaining voltage parameters of multiple battery subgroups, and determining abnormal battery subgroups according to the voltage parameters of the battery subgroups; obtaining a pressure difference change curve within the abnormal battery subgroup, and determining abnormal cells according to the pressure difference change curve and outputting identification results. The present invention collects voltage parameters at preset time and preset working conditions, and compares the relationship between the pressure difference between battery subgroups and between single cells and single cells with preset values, thereby achieving preliminary screening of abnormal battery subgroups; and by comparing the pressure difference change curve between abnormal battery subgroups and normal battery subgroups, rapid identification of abnormal cells is achieved. The present invention does not require a huge data base, does not require complex calculations, and is simple and efficient.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a method, system, device and medium for locating and identifying abnormal cells in a battery pack. Background Art

[0002] As the core component of new energy vehicles, power batteries are directly related to the safe and stable driving of vehicles. Due to the fact that the battery manufacturing process does not meet the ideal requirements and the uneven temperature distribution of the battery pack, the status of different cells in the same vehicle cannot be completely consistent. If the abnormality of the battery cell cannot be identified in time, the battery cell problem of the battery pack will become more and more serious as the vehicle is used, and may even cause problems such as car stalling and battery leakage, endangering driving safety.

[0003] The prior art method for identifying abnormal cells requires huge amounts of data for analysis and calculation, which is not conducive to rapid identification of abnormal cells. The present invention can rapidly identify abnormal battery subgroups, and then identify abnormal cells within the abnormal battery subgroups, thereby improving identification efficiency. Summary of the invention

[0004] In view of the defects in the prior art, the present invention provides a method, system, device and medium for locating and identifying abnormal cells in a battery pack.

[0005] In a first aspect, a method for locating and identifying abnormal cells in a battery pack is provided, wherein the battery pack includes a plurality of battery sub-groups, and the method includes:

[0006] Acquire voltage parameters of multiple battery subgroups, and determine abnormal battery subgroups according to the voltage parameters of the battery subgroups; wherein the voltage parameters include single cell voltage, average single cell voltage, group voltage, and average group voltage;

[0007] The pressure difference variation curve within the abnormal battery subgroup is obtained, and the abnormal battery cell is determined according to the pressure difference variation curve and the identification result is output.

[0008] Preferably, the method for obtaining the voltage parameters of the plurality of battery subgroups is: obtaining the voltage parameters at the charging end or the discharging end at a preset time.

[0009] Preferably, determining the abnormal battery subgroup according to the voltage parameters of the battery subgroup includes:

[0010] Calculating a group difference between a group voltage of a battery subgroup and an average group voltage, and if the group difference is greater than a preset group difference, determining that the battery subgroup may be abnormal;

[0011] The cell difference between the cell voltage of each battery cell in the battery subgroup and the average cell voltage is calculated. If the cell difference is greater than a preset cell difference and the number of battery cells having a cell difference greater than the preset difference is greater than a preset number, it is determined that the battery subgroup is abnormal.

[0012] Preferably, obtaining a pressure difference change curve within an abnormal battery subgroup, determining an abnormal battery cell according to the pressure difference change curve and outputting an identification result comprises:

[0013] Fitting the abnormal voltage difference change curve within the battery subgroup according to the voltage parameters at the charging end or the discharging end at the preset time;

[0014] Obtaining the peak value number and the maximum peak value of the corresponding single battery cell in the voltage difference change curve, and determining whether the peak value number is greater than a preset peak value number and the maximum peak value is greater than a preset peak value;

[0015] If so, output the judgment result.

[0016] In a second aspect, a battery pack abnormal cell positioning and identification system includes:

[0017] A first identification module is used to obtain voltage parameters of multiple battery subgroups and determine abnormal battery subgroups according to the voltage parameters of the battery subgroups;

[0018] The second identification module obtains a pressure difference variation curve within the abnormal battery subgroup, determines the abnormal battery cell according to the pressure difference variation curve, and outputs an identification result.

[0019] Preferably, the first identification module includes: the voltage parameter is a voltage parameter of a charging end or a discharging end within a preset time.

[0020] Preferably, the second identification module includes:

[0021] A first judgment module is used to calculate a group difference between a group voltage of a battery subgroup and an average group voltage, and if the group difference is greater than a preset group difference, it is judged that the battery subgroup may be abnormal;

[0022] The second judgment module calculates the cell difference between the cell voltage of each battery cell in the battery subgroup and the average cell voltage. If the cell difference is greater than a preset cell difference and the number of battery cells whose cell difference is greater than the preset difference is greater than a preset number, it is judged that the battery subgroup is abnormal.

[0023] Preferably, the second identification module includes:

[0024] Processing module: used to fit the abnormal voltage difference change curve within the battery subgroup according to the voltage parameters at the charging end or the discharging end at a preset time;

[0025] A third judgment module: used to obtain the peak number and maximum peak value of the corresponding single cell in the voltage difference change curve, and judge whether the peak number is greater than the preset peak number and the maximum peak value is greater than the preset peak value;

[0026] Output module: used to output judgment results.

[0027] According to a third aspect, an electronic device includes a memory and a processor, wherein the memory stores a computer program, the computer program is configured to be executed by the processor, and the computer program includes instructions for executing any of the above methods.

[0028] In a fourth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a computer, any of the above methods is implemented.

[0029] The beneficial effects of the present invention are as follows: the present invention realizes preliminary screening of abnormal battery subgroups by collecting voltage parameters of preset time and preset working conditions, comparing the relationship between the voltage difference between battery subgroups and between single cells and single cells and preset values; and realizes rapid identification of abnormal cells by comparing the change curve of the voltage difference between abnormal battery subgroups and normal battery subgroups. The present invention does not require a huge data base or complex calculations, and is simple and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0031] Figure 1 is a flow chart of a method according to an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the structure of the system of Embodiment 2 of the present invention;

[0033] Figure 3 It is a schematic diagram of the structure of the device of embodiment 3 of the present invention. DETAILED DESCRIPTION

[0034] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0035] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by those skilled in the art to which the present invention belongs.

[0036] Embodiment 1

[0037] like Figure 1As shown, an embodiment of the present invention provides a method for locating and identifying abnormal cells in a battery pack, wherein the battery pack includes a plurality of battery sub-groups, and the method includes:

[0038] Obtaining voltage parameters of multiple battery subgroups, and determining abnormal battery subgroups according to the voltage parameters of the battery subgroups; wherein,

[0039] Since the temperature is greatly affected by the temperature control system, which involves the system structure, and the impact of non-extreme temperature on the battery cell is very complex and is a long-term cumulative impact that requires huge data for analysis, the present invention directly collects single cell voltage and group voltage data as the main data used by the present invention.

[0040] Specifically, the voltage parameters are voltage parameters at the charging end or the discharging end at a preset time, and the voltage parameters include single cell voltage, average single cell voltage, group voltage, and average group voltage; the single cell voltage and group voltage can be real-time voltages at any time within the preset time.

[0041] Only the voltage data of the preset time and preset working conditions are collected to ensure that the basic data can meet the calculation requirements while reducing the basic data collection and processing time, further reducing the amount of calculation and improving recognition efficiency.

[0042] Specifically, determining the abnormal battery subgroup according to the voltage parameters of the battery subgroup includes:

[0043] Calculating a group difference between a group voltage of a battery subgroup and an average group voltage, and if the group difference is greater than a preset group difference, determining that the battery subgroup may be abnormal;

[0044] The cell difference between the cell voltage of each battery cell in the battery subgroup and the average cell voltage is calculated. If the cell difference is greater than a preset cell difference and the number of battery cells having a cell difference greater than the preset difference is greater than a preset number, it is determined that the battery subgroup is abnormal.

[0045] Through the relationship between the voltage difference between battery subgroups and between single cells and the preset value, the preliminary screening of abnormal batteries is achieved, the amount of calculation is reduced, and the identification range is further narrowed.

[0046] Specifically, obtaining a pressure difference change curve within an abnormal battery subgroup, determining an abnormal battery cell according to the pressure difference change curve and outputting an identification result includes:

[0047] Fitting the abnormal voltage difference change curve within the battery subgroup according to the voltage parameters at the charging end or the discharging end at the preset time;

[0048] Obtaining the peak value number and the maximum peak value of the corresponding single battery cell in the voltage difference change curve, and determining whether the peak value number is greater than a preset peak value number and the maximum peak value is greater than a preset peak value;

[0049] If so, output the judgment result.

[0050] In particular, for some abnormal battery subgroups, at the end of charging and discharging, their pressure difference change curve (frequency distribution diagram) is different from that of normal batteries. Under normal circumstances, the pressure difference change curve of the battery at the end of charging and discharging has one and only one peak that meets a certain threshold, while for abnormal battery subgroups, their pressure difference change curve has one peak that meets a certain threshold and multiple small peaks, and the pressure difference corresponding to the multiple small peaks is the pressure difference of the abnormal battery. In a specific embodiment, when an abnormal battery is identified, the number of the abnormal battery will be automatically identified, and the number includes the group number and the number within the group, so that the abnormal battery can be quickly located and the service life of the battery can be improved.

[0051] In summary, the present invention achieves preliminary screening of abnormal battery subgroups by collecting voltage parameters of preset time and preset working conditions, comparing the relationship between the voltage difference between battery subgroups and between single cells and single cells and preset values; and achieves rapid identification of abnormal cells by comparing the change curve of the voltage difference between abnormal battery subgroups and normal battery subgroups. The present invention does not require a huge data base or complex calculations, and is simple and efficient.

[0052] Embodiment 2

[0053] like Figure 2 As shown, an embodiment of the present invention provides a battery pack abnormal cell positioning and identification system, comprising:

[0054] A first identification module is used to obtain voltage parameters of multiple battery subgroups and determine abnormal battery subgroups according to the voltage parameters of the battery subgroups;

[0055] The second identification module is used to obtain a voltage difference variation curve of an abnormal battery subgroup, determine an abnormal battery cell according to the voltage difference variation curve, and output an identification result.

[0056] Preferably, the first identification module includes: the voltage parameter is a voltage parameter of a charging end or a discharging end within a preset time.

[0057] Specifically, the second identification module includes:

[0058] A first judgment module is used to calculate a group difference between a group voltage of a battery subgroup and an average group voltage, and if the group difference is greater than a preset group difference, it is judged that the battery subgroup may be abnormal;

[0059] The second judgment module calculates the cell difference between the cell voltage of each battery cell in the battery subgroup and the average cell voltage. If the cell difference is greater than a preset cell difference and the number of battery cells whose cell difference is greater than the preset difference is greater than a preset number, it is judged that the battery subgroup is abnormal.

[0060] Specifically, the second identification module includes:

[0061] Processing module: used to fit the abnormal voltage difference change curve within the battery subgroup according to the voltage parameters at the charging end or the discharging end at a preset time;

[0062] A third judgment module: used to obtain the peak number and maximum peak value of the corresponding single cell in the voltage difference change curve, and judge whether the peak number is greater than the preset peak number and the maximum peak value is greater than the preset peak value;

[0063] Output module: used to output judgment results.

[0064] A battery pack abnormal cell positioning and identification system provided in an embodiment of the present invention and a battery pack abnormal cell positioning and identification method provided in the above embodiment are based on the same inventive concept. Therefore, for more specific working processes of each module in this embodiment, reference can be made to the corresponding contents disclosed in the above embodiment, which will not be repeated here.

[0065] Embodiment 3

[0066] like Figure 3 As shown, this embodiment provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, the computer program is configured to be executed by the processor, and the computer program includes instructions for executing any of the methods described in the above embodiments.

[0067] It should be understood that in the embodiment of the present invention, the processor may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0068] In the embodiment of the present invention, the memory may include a read-only memory and a random access memory, and provide instructions and data to the processor. A portion of the memory may also include a non-volatile random access memory. For example, the memory may also store information about the device type.

[0069] Embodiment 4

[0070] This embodiment provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program. When the computer program is executed by a computer, the method described in any one of the above embodiments is implemented.

[0071] The computer-readable storage medium may be a memory of the identification device provided in the aforementioned embodiment, such as a hard disk or memory of the identification device. The computer-readable storage medium may also be an external memory of the device, such as a plug-in hard disk, a smart memory card (SmartMediaCard, SMC), a secure digital (SecureDigital, SD) card, a flash card (FlashCard), etc. equipped on the identification device. Furthermore, the computer-readable storage medium may also include both an internal memory and an external memory of the identification device. The computer-readable storage medium is used to store the computer program and other programs and data. The computer-readable storage medium may also be used to temporarily store data that has been output or is to be output.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A method for locating and identifying abnormal cells in a battery pack, wherein the battery pack comprises a plurality of battery sub-groups, characterized in that: The method comprises: Obtain voltage parameters of multiple battery subgroups, and determine abnormal battery subgroups according to the voltage parameters of the battery subgroups, wherein determining the abnormal battery subgroup according to the voltage parameters of the battery subgroups includes calculating the group difference between the group voltage of the battery subgroup and the average group voltage, and if the group difference is greater than a preset group difference, it is determined that the battery subgroup may be abnormal; calculating the cell difference between the single cell voltage of each battery cell in the battery subgroup and the average single cell voltage, and if the single cell difference is greater than a preset single cell difference and the number of single cells with a single cell difference greater than the preset difference is greater than a preset number, it is determined that the battery subgroup is abnormal; wherein the voltage parameters include single cell voltage, average single cell voltage, group voltage, and average group voltage; and the method for obtaining the voltage parameters of multiple battery subgroups is: obtaining the voltage parameters at the charging end or the discharging end of a preset time; Obtain a pressure difference change curve of an abnormal battery subgroup, determine the abnormal battery cell according to the pressure difference change curve and output an identification result, wherein the pressure difference change curve in the abnormal battery subgroup is fitted according to the voltage parameters at the charging end or the discharging end at a preset time; obtain the number of peak values ​​and the maximum peak value of the corresponding single battery cell in the pressure difference change curve, and judge whether the number of peak values ​​is greater than the preset number of peak values ​​and the maximum peak value is greater than the preset peak value; if so, output the judgment result.

2. A battery pack abnormal cell positioning and identification system, characterized in that: include: A first identification module, used to obtain voltage parameters of multiple battery subgroups, and determine abnormal battery subgroups according to the voltage parameters of the battery subgroups, wherein the first identification module includes: the voltage parameter is a voltage parameter of a charging end or a discharging end within a preset time; A second identification module, which obtains a pressure difference change curve within an abnormal battery subgroup, determines an abnormal battery cell according to the pressure difference change curve, and outputs an identification result; Wherein, the second identification module includes: A first judgment module is used to calculate a group difference between a group voltage of a battery subgroup and an average group voltage, and if the group difference is greater than a preset group difference, it is judged that the battery subgroup may be abnormal; A second judgment module calculates a cell difference between a cell voltage of each cell in the battery subgroup and an average cell voltage, and if the cell difference is greater than a preset cell difference and the number of cells whose cell difference is greater than the preset difference is greater than a preset number, then it is judged that the battery subgroup is abnormal; Processing module: used to fit the abnormal voltage difference change curve within the battery subgroup according to the voltage parameters at the charging end or the discharging end at a preset time; A third judgment module: used to obtain the peak number and maximum peak value of the corresponding single cell in the voltage difference change curve, and judge whether the peak number is greater than the preset peak number and the maximum peak value is greater than the preset peak value; Output module: used to output judgment results.

3. An electronic device, characterized in that: The invention comprises a memory and a processor, wherein the memory stores a computer program, the computer program is configured to be executed by the processor, and the computer program comprises instructions for executing the method of claim 1.

4. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a computer, the method of claim 1 is implemented.

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