CN116087799A - Battery module internal consistency monitoring method, system, storage medium and terminal - Google Patents

Abstract

The invention provides a method, a system, a storage medium and a terminal for monitoring the internal consistency of a battery module, which comprise the following steps: acquiring voltage data of each battery core in the battery module; preprocessing the voltage data; calculating statistical parameters of all the preprocessed voltage data; the statistical parameter is variance or standard deviation; calculating statistical parameters of residual voltage data after removing the voltage data for each preprocessed voltage data; for each preprocessed voltage data, calculating the difference value between the statistical parameters of all the voltage data and the statistical parameters of the residual voltage data; and judging whether the consistency problem exists in the battery module based on the difference value. According to the method, the system, the storage medium and the terminal for monitoring the internal consistency of the battery module, the judgment of the internal consistency of the battery module is realized through the statistical analysis of the cell voltage, and the operation safety of the battery module is effectively improved.

Description

Battery module internal consistency monitoring method, system, storage medium and terminal

technical field

The invention relates to the technical field of battery modules, in particular to a battery module internal consistency monitoring method, system, storage medium and terminal.

Background technique

During the rapid development of energy storage technology, energy storage safety has always been a hot issue in the industry. How to ensure the safety of the energy storage battery used in the energy storage power station is particularly important. In order to ensure the safety of the battery, if the internal operation of the battery can be intelligently supervised during daily operation, the internal The data is divided into a level of confusion. In the daily inspection, the supervision and operation and maintenance of the more chaotic batteries are strengthened, and the corresponding operation and maintenance measures are coordinated to realize the close attention to the operation status of the batteries, so as to avoid possible risks such as combustion and explosion.

Whether it is an energy storage battery or a battery for new energy vehicles, its consistency change is the main factor for battery safety. Ideally, all cells in a battery module should perform identically. However, due to the different production environment and production process, the cells in the same battery module will also have large or small differences. This inconsistency is exacerbated as battery packs are used. Once the battery module is inconsistent, it will cause problems such as capacity reduction. In severe cases, it will endanger the safety of the battery, causing risks such as short circuit, combustion, and explosion.

However, the existing battery management system (Battery Management System, BMS) cannot distinguish the consistency degree of the battery, and can only perform simple overvoltage, undervoltage diagnosis, and differential pressure alarm. Therefore, there is an urgent need for a method that can determine the degree of internal consistency of the battery.

Contents of the invention

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a battery module internal consistency monitoring method, system, storage medium and terminal, and realize the judgment of the internal consistency of the battery module through the statistical analysis of the battery voltage , effectively improving the safety of the battery module operation.

In a first aspect, the present invention provides a method for monitoring the internal consistency of a battery module, comprising the following steps: obtaining voltage data of each cell in the battery module; preprocessing the voltage data; Data, calculate the statistical parameters of all the voltage data; the statistical parameters are variance or standard deviation; for each voltage data after preprocessing, calculate the statistical parameters of the remaining voltage data after removing the voltage data; for preprocessing For each last voltage data, calculate the difference between the statistical parameters of all the voltage data and the statistical parameters of the remaining voltage data; judge whether there is a consistency problem inside the battery module based on the difference.

In an implementation manner of the first aspect, preprocessing the voltage data includes the following steps:

removing abnormal values in the voltage data;

Deduplication processing is performed on the voltage data according to the acquisition time of the voltage data.

In an implementation manner of the first aspect, judging whether there is a consistency problem inside the battery module based on the difference includes the following steps:

set the threshold;

When the deviation is greater than the threshold, it is judged that there is a consistency problem inside the battery module; otherwise, it is judged that there is no consistency problem inside the battery module.

In an implementation manner of the first aspect, when it is judged that there is a consistency problem inside the battery module, it also includes determining the abnormal value in the difference by the 3σ rule, and determining the battery cell corresponding to the abnormal value It is an abnormal cell.

In an implementation manner of the first aspect, when it is judged that there is a consistency problem inside the battery module, it further includes determining the abnormal value in the difference by using the box plot method, and determining the corresponding value of the abnormal value. The cell is the abnormal cell.

In a second aspect, the present invention provides a battery module internal consistency monitoring system, including an acquisition module, a preprocessing module, a first calculation module, a second calculation module, a third calculation module, and a judgment module;

The acquisition module is used to acquire the voltage data of each cell in the battery module;

The preprocessing module is used to preprocess the voltage data;

The first calculation module is used to calculate statistical parameters of all the voltage data after preprocessing; the statistical parameters are variance or standard deviation;

The second calculation module is used for calculating, for each preprocessed voltage data, statistical parameters of the remaining voltage data after removing the voltage data;

The third calculating module is used for calculating the difference between the statistical parameters of all the voltage data and the statistical parameters of the remaining voltage data for each preprocessed voltage data;

The judging module is used to judge whether there is a consistency problem inside the battery module based on the difference.

In a third aspect, the present invention provides a storage medium on which a computer program is stored, and when the program is executed by a processor, the above method for monitoring internal consistency of a battery module is implemented.

In a fourth aspect, the present invention provides a battery module internal consistency monitoring terminal, including: a processor and a memory;

The memory is used to store computer programs;

The processor is used to execute the computer program stored in the memory, so that the battery module internal consistency monitoring terminal executes the above battery module internal consistency monitoring method.

As mentioned above, the battery module internal consistency monitoring method, system, storage medium and terminal of the present invention have the following

Beneficial effect:

(1) Based on the voltage data of each battery cell in the battery module, a small amount of data can be used to judge the internal consistency of the battery module, which effectively improves the safety of the battery module operation;

(2) It can accurately locate the cells that affect the consistency of the battery module;

(3) It is suitable for batteries of different models, different manufacturers, and different working conditions, with a wide range of applications, and is suitable for the entire life cycle of the battery;

(4) Compared with the pressure difference judgment of BMS, it is more effective and can quantify the degree of consistency;

(5) In addition to being applicable to a single battery module, it is also applicable to multiple battery modules in series working conditions to judge the consistency of batteries between different battery modules in series mode, avoiding complicated operations such as unpacking.

Description of drawings

FIG. 1 shows a flow chart of an embodiment of the battery module internal consistency monitoring method of the present invention;

Fig. 2 shows the schematic diagram of the voltage data of the cell in an embodiment of the present invention changing with time;

FIG. 3 shows a schematic diagram of the variation with time of the variance of the voltage data of the cell of the present invention in an embodiment;

FIG. 4 is a schematic structural diagram of an embodiment of the battery module internal consistency monitoring system of the present invention;

FIG. 5 is a schematic structural diagram of an embodiment of a battery module internal consistency monitoring terminal according to the present invention.

Component designation description

41 Get module

42 Preprocessing module

43 The first computing module

44 The second computing module

45 The third calculation module

46 Judgment module

51 processors

52 memory

Detailed ways

Embodiments of the present invention are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, in the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

It should be noted that the diagrams provided in the following embodiments are only schematically illustrating the basic ideas of the present invention, and only the components related to the present invention are shown in the diagrams rather than the number, shape and shape of the components in actual implementation. Dimensional drawing, the type, quantity and proportion of each component can be changed arbitrarily during actual implementation, and the component layout type may also be more complicated.

The battery module internal consistency monitoring method, system, storage medium and terminal of the present invention can realize accurate judgment of the internal consistency of the battery module through the statistical analysis of the cell voltage, and can monitor the consistency of the battery module. Accurate positioning of the battery cells enables reliable monitoring of the battery module and effectively improves the safety of the battery module operation.

As shown in FIG. 1, in one embodiment, the battery module internal consistency monitoring method of the present invention includes the following steps:

Step S1, acquiring voltage data of each battery cell in the battery module.

Specifically, the current-time data I(t) and the voltage-time data V(t) of all batteries in the daily working conditions of the battery module are collected. Figure 2 shows the voltage data as a function of time.

Step S2, performing preprocessing on the voltage data.

Specifically, in order to improve the validity of the voltage data, the voltage data needs to be preprocessed. Wherein, abnormal values in the voltage data need to be removed, and deduplication processing is performed on the voltage data according to the collection time of the voltage data, so as to obtain effective voltage data.

Step S3. For all the preprocessed voltage data, calculate statistical parameters of all the voltage data; the statistical parameters are variance or standard deviation.

Specifically, variance is a measure of how dispersed a random variable or set of data is when measured in probability theory and statistics. The standard deviation is the arithmetic square root of the variance. Standard deviation can reflect the degree of dispersion of a data set. Therefore, the present invention firstly calculates the variance or standard deviation of all the voltage data obtained after preprocessing, so as to be used for subsequent battery module consistency judgment. FIG. 3 is a schematic diagram of variance of voltage data changing with time.

Step S4. For each preprocessed voltage data, calculate statistical parameters of the remaining voltage data after removing the voltage data.

Specifically, for each preprocessed voltage data, after removing itself, the variance or standard deviation of the remaining voltage data is calculated.

Step S5 , for each preprocessed voltage data, calculate the difference between the statistical parameters of all the voltage data and the statistical parameters of the remaining voltage data.

Specifically, the variance or standard deviation of all the voltage data is subtracted from the variance or standard deviation of the remaining voltage data to obtain the corresponding difference. Combine all differences to get a sequence of differences.

Step S6 , judging whether there is a consistency problem inside the battery module based on the difference.

Specifically, in the present invention, it is judged whether there is a consistency problem inside the battery module by comparing the difference with a preset threshold.

In one embodiment, judging whether there is a consistency problem inside the battery module based on the difference includes the following steps:

61) Set the threshold.

Wherein, the threshold can be customized according to actual application scenarios.

62) When the deviation is greater than the threshold, it is judged that there is a consistency problem inside the battery module; otherwise, it is judged that there is no consistency problem inside the battery module.

Among them, the difference obtained by removing abnormal cells will be larger in value than the difference obtained by removing non-abnormal cells, and the difference may be several times. Therefore, when the deviation is greater than the threshold, it can be determined that there is a consistency problem inside the battery module.

When judging that there is an inconsistency problem inside the battery module, in order to further locate the abnormal cell, use the 3σ rule or the box diagram method to determine the abnormal value in the difference, then the cell corresponding to the abnormal value is Abnormal battery.

As shown in Figure 4, in one embodiment, the battery module internal consistency monitoring system of the present invention includes an acquisition module 41, a preprocessing module 42, a first calculation module 43, a second calculation module 44, and a third calculation module 45 And judgment module 46.

The acquisition module 41 is used to acquire the voltage data of each cell in the battery module.

Specifically, the current-time data I(t) and the voltage-time data V(t) of all batteries in the daily working conditions of the battery module are collected. Figure 2 shows the voltage data as a function of time.

The preprocessing module 42 is connected to the acquisition module 41 and is used for preprocessing the voltage data.

Specifically, in order to improve the validity of the voltage data, the voltage data needs to be preprocessed. Wherein, abnormal values in the voltage data need to be removed, and deduplication processing is performed on the voltage data according to the collection time of the voltage data, so as to obtain valid voltage data.

The first calculating module 43 is connected to the preprocessing module 42, and is used for calculating statistical parameters of all the voltage data after preprocessing; the statistical parameters are variance or standard deviation.

Specifically, variance is a measure of how dispersed a random variable or set of data is when measured in probability theory and statistics. The standard deviation is the arithmetic square root of the variance. Standard deviation can reflect the degree of dispersion of a data set. Therefore, the present invention firstly calculates the variance or standard deviation of all the voltage data obtained after preprocessing, so as to be used for subsequent battery module consistency judgment. FIG. 3 is a schematic diagram of variance of voltage data changing with time.

The second calculating module 44 is connected to the preprocessing module 42, and is used for calculating statistical parameters of the remaining voltage data after removing the voltage data for each preprocessed voltage data.

Specifically, for each preprocessed voltage data, after removing itself, the variance or standard deviation of the remaining voltage data is calculated.

The third calculation module 45 is connected to the first calculation module 43 and the second calculation module 44, and is used for calculating the statistical parameters of all the voltage data and the remaining The difference of the statistical parameters of the voltage data.

Specifically, the variance or standard deviation of all the voltage data is subtracted from the variance or standard deviation of the remaining voltage data to obtain the corresponding difference. Combine all differences to get a sequence of differences.

The judging module 46 is connected to the third computing module 45, and is used for judging whether there is a consistency problem inside the battery module based on the difference.

Specifically, in the present invention, it is judged whether there is a consistency problem inside the battery module by comparing the difference with a preset threshold.

In one embodiment, judging whether there is a consistency problem inside the battery module based on the difference includes the following steps:

61) Set the threshold.

Wherein, the threshold can be customized according to actual application scenarios.

62) When the deviation is greater than the threshold, it is judged that there is a consistency problem inside the battery module; otherwise, it is judged that there is no consistency problem inside the battery module.

Among them, the difference obtained by removing abnormal cells will be larger in value than the difference obtained by removing non-abnormal cells, and the difference may be several times. Therefore, when the deviation is greater than the threshold, it can be determined that there is a consistency problem inside the battery module.

When judging that there is an inconsistency problem inside the battery module, in order to further locate the abnormal cell, use the 3σ rule or the box diagram method to determine the abnormal value in the difference, then the cell corresponding to the abnormal value is Abnormal battery.

It should be noted that it should be understood that the division of each module of the above device is only a division of logical functions, and may be fully or partially integrated into one physical entity or physically separated during actual implementation. Moreover, these modules can be implemented in the form of calling software through processing elements, or can be implemented in the form of hardware, or some modules can be implemented in the form of calling software through processing elements, and some modules can be implemented in the form of hardware. For example, the x module can be a separate processing element, and can also be integrated in a chip of the above-mentioned device. In addition, the x module can also be stored in the memory of the above-mentioned device in the form of program code, and can be invoked by a certain processing element of the above-mentioned device to execute the function of the above-mentioned x module. The implementation of other modules is similar. All or part of these modules can be integrated together, and can also be implemented independently. The processing element mentioned here may be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each module above can be completed by an integrated logic circuit of hardware in the processor element or an instruction in the form of software. The above modules may be one or more integrated circuits configured to implement the above method, for example: one or more specific integrated circuits (Application Specific Integrated Circuit, referred to as ASIC), one or more microprocessors (Digital Signal Processor, DSP for short), one or more Field Programmable Gate Arrays (Field Programmable Gate Array, FPGA for short), etc. When one of the above modules is implemented in the form of a processing element scheduling program code, the processing element may be a general-purpose processor, such as a central processing unit (Central Processing Unit, CPU for short) or other processors that can call program codes. These modules can be integrated together and implemented in the form of a System-on-a-chip (SOC for short).

The storage medium of the present invention stores a computer program, and when the program is executed by a processor, the above method for monitoring the internal consistency of the battery module is realized. Preferably, the storage medium includes: various media capable of storing program codes such as ROM, RAM, magnetic disk, U disk, memory card or optical disk.

As shown in FIG. 5 , in one embodiment, the battery module internal consistency monitoring terminal of the present invention includes: a processor 51 and a memory 52 .

The memory 52 is used to store computer programs. The memory 52 includes various media capable of storing program codes such as ROM, RAM, magnetic disk, U disk, memory card or optical disk.

The processor 51 is connected to the memory 52 and is used to execute the computer program stored in the memory, so that the battery module internal consistency monitoring terminal executes the above battery module internal consistency monitoring method.

Preferably, the processor can be a general-purpose processor, including a central processing unit (Central Processing Unit, referred to as CPU), a network processor (Network Processor, referred to as NP), etc.; it can also be a digital signal processor (Digital Signal Processor, referred to as DSP), Application Specific Integrated Circuit (ASIC for short), Field Programmable Gate Array (Field Programmable Gate Array, FPGA for short) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

To sum up, the battery module internal consistency monitoring method, system, storage medium and terminal of the present invention are based on the voltage data of each battery cell in the battery module, and can use a small amount of data to realize the judgment of the internal consistency of the battery module, effectively It improves the safety of the battery module operation; it can accurately locate the battery cells that affect the consistency of the battery module; it is suitable for batteries of different models, different manufacturers, and different working conditions. It has a wide range of applications and is suitable for batteries The whole life cycle; Compared with BMS, the pressure difference judgment is more effective, and can quantify the degree of consistency; in addition to being applicable to a single battery module, it is also applicable to multiple battery modules in series working conditions to judge the series mode. The consistency of batteries among different battery modules avoids complex operations such as unpacking. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial application value.

The above-mentioned embodiments only illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the present invention should still be covered by the claims of the present invention.

Claims (8)

1. A battery module internal consistency monitoring method, characterized in that: comprising the following steps: Obtain the voltage data of each cell in the battery module; Preprocessing the voltage data; For all the voltage data after preprocessing, calculate the statistical parameters of all the voltage data; the statistical parameters are variance or standard deviation; For each voltage data after preprocessing, calculate statistical parameters of the remaining voltage data after removing the voltage data; For each preprocessed voltage data, calculating the difference between the statistical parameters of all the voltage data and the statistical parameters of the remaining voltage data; Based on the difference, it is judged whether there is a consistency problem inside the battery module. 2. The method for monitoring internal consistency of a battery module according to claim 1, wherein the preprocessing of the voltage data comprises the following steps: removing abnormal values in the voltage data; Deduplication processing is performed on the voltage data according to the acquisition time of the voltage data. 3. The method for monitoring internal consistency of a battery module according to claim 1, wherein judging whether there is a consistency problem inside the battery module based on the difference comprises the following steps: set the threshold; When the deviation is greater than the threshold, it is judged that there is a consistency problem inside the battery module; otherwise, it is judged that there is no consistency problem inside the battery module. 4. The internal consistency monitoring method of the battery module according to claim 1, characterized in that: when it is judged that there is a consistency problem inside the battery module, it also includes determining the abnormal value in the difference by the 3σ rule , and determine that the cell corresponding to the abnormal value is the abnormal cell. 5. The method for monitoring the internal consistency of the battery module according to claim 1, characterized in that: when it is judged that there is a consistency problem inside the battery module, it also includes determining the difference in the difference by the box plot method abnormal value, and determine that the cell corresponding to the abnormal value is the abnormal cell. 6. A battery module internal consistency monitoring system, characterized in that it includes an acquisition module, a preprocessing module, a first calculation module, a second calculation module, a third calculation module and a judgment module; The acquisition module is used to acquire the voltage data of each cell in the battery module; The preprocessing module is used to preprocess the voltage data; The first calculation module is used to calculate statistical parameters of all the voltage data after preprocessing; the statistical parameters are variance or standard deviation; The second calculation module is used for calculating, for each preprocessed voltage data, statistical parameters of the remaining voltage data after removing the voltage data; The third calculating module is used for calculating the difference between the statistical parameters of all the voltage data and the statistical parameters of the remaining voltage data for each preprocessed voltage data; The judging module is used to judge whether there is a consistency problem inside the battery module based on the difference. 7. A storage medium, on which a computer program is stored, wherein when the program is executed by a processor, the internal consistency monitoring method of the battery module according to any one of claims 1 to 5 is implemented. 8. A battery module internal consistency monitoring terminal, comprising: a processor and a memory; The memory is used to store computer programs; The processor is used to execute the computer program stored in the memory, so that the battery module internal consistency monitoring terminal executes the battery module internal consistency monitoring method according to any one of claims 1 to 5.

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