CN116298998B

CN116298998B - Battery cell detection method and device, electronic equipment and storage medium

Info

Publication number: CN116298998B
Application number: CN202310604579.1A
Authority: CN
Inventors: 左启琪; 李伟; 吴凯; 李茂华; 耿慧慧
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2023-05-26
Filing date: 2023-05-26
Publication date: 2023-10-20
Anticipated expiration: 2043-05-26
Also published as: CN116298998A

Abstract

The application discloses a battery cell detection method, a battery cell detection device, electronic equipment and a storage medium. The battery cell detection method comprises the following steps: responding to a variable frequency excitation pulse signal applied to a battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in each frequency domain; and obtaining a battery cell detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in each frequency domain. The battery cell detection method provided by the embodiment of the application can improve the accuracy of the cell detection result.

Description

Battery cell detection method and device, electronic equipment and storage medium

Technical Field

The application relates to the technical field of batteries, in particular to a battery cell detection method and device, electronic equipment and a storage medium.

Background

After the battery is assembled, the battery cells of the battery are usually required to be detected to screen out some battery cells with abnormal battery cells. Currently, for detecting a battery cell of a battery, an ac impedance of the battery cell is generally calculated, so as to determine whether the battery cell is abnormal according to a calculation result of the ac impedance.

However, since the battery cell is generally a winding structure, the winding structure affects the high-frequency ac inductance, and thus the battery cell detection method is prone to misjudgment of the battery cell detection result.

Disclosure of Invention

In view of the above problems, the present application provides a method, an apparatus, an electronic device, and a storage medium for detecting a battery cell, which can improve the accuracy of the cell detection result.

In a first aspect, the present application provides a method for detecting a battery cell, the method comprising: responding to a variable frequency excitation pulse signal applied to a battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in each frequency domain; obtaining a battery cell detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in each frequency domain; the variable-frequency excitation pulse signals comprise a plurality of excitation pulse signals, wherein the variable-frequency excitation pulse signals have excitation pulse signal interval duration with different duration, and the excitation pulse signal interval duration is interval duration between adjacent excitation pulse signals.

According to the technical scheme, the voltage change data of the to-be-detected battery cell, to which the variable frequency excitation pulse signal is applied, in each frequency domain is obtained, so that the characteristic that the voltage change data of the normal battery cell in each frequency domain is different from the voltage change data of the abnormal battery cell in each frequency domain is utilized, and whether the to-be-detected battery cell is abnormal or not is judged through the voltage change data of the to-be-detected battery cell in each frequency domain, so that the detection cost required by detecting the battery cell is reduced, the influence of a battery cell structure on a battery cell detection result is reduced, and the accuracy of the battery cell detection result is improved.

In some embodiments, obtaining voltage variation data of a to-be-measured cell according to an excitation pulse signal applied to the to-be-measured cell includes: and responding to the variable frequency excitation pulse signal applied to the battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in a first frequency domain and a second frequency domain. Therefore, the battery cell detection results of the battery cell to be detected in the first frequency domain and the second frequency domain can be obtained according to the voltage change data of the battery cell to be detected in the first frequency domain and the second frequency domain, and further whether the battery cell abnormality belongs to the first frequency domain or the second frequency domain can be rapidly judged, and abnormality positioning is achieved.

Determining the interval duration of the excitation pulse signals of the first frequency domain and the second frequency domain according to the chemical self-discharge duration required by the normal cell to consume the excitation pulse signals; the excitation pulse signal interval time length of the second frequency domain is longer than that of the first frequency domain. Under the condition that variable frequency excitation pulse signals are sequentially applied to the battery core to be tested, the interval duration of the excitation pulse signals of the first frequency domain/the second frequency domain is determined according to the chemical self-discharge duration required by the consumption excitation pulse signals of the normal battery core, and the interval duration of the excitation pulse signals of the second frequency domain is longer than the interval duration of the excitation pulse signals of the first frequency domain, so that after the variable frequency excitation pulse signals are applied to the battery core to be tested, voltage change data of the battery core to be tested in the first frequency domain corresponding to an electronic transmission process and voltage change data of the battery core to be tested in the second frequency domain corresponding to an ion transmission process and a charge transfer process can be obtained, and the abnormal location can be quickly performed by utilizing the frequency domain corresponding to the abnormality when the battery core is determined to be abnormal in the follow-up process.

In some embodiments, the excitation pulse signal interval duration of the first frequency domain is less than the chemical self-discharge duration required by a normal cell to consume the excitation pulse signal, and the excitation pulse signal interval duration of the second frequency domain is greater than the chemical self-discharge duration. Therefore, a first frequency domain corresponding to the electron transmission process and a second frequency domain corresponding to the ion transmission process and the charge transfer process can be accurately divided, so that the subsequent abnormal positioning is more accurate.

In some embodiments, the excitation pulse signal interval time of the variable frequency excitation pulse signal is greater than or equal to the physical self-discharge time period required by the abnormal cell to consume the excitation pulse signal. Therefore, after the interval duration of the excitation pulse signals of the variable frequency excitation pulse signals is set to be not less than the physical self-discharge duration required by the consumption excitation pulse signals of the abnormal battery cells, whether the battery cells to be detected are abnormal or not can be judged by judging whether the voltage change data of the battery cells to be detected in the first frequency domain is reduced or in a stable state under the condition that the variable frequency excitation pulse signals are applied to the battery cells to be detected, and the accuracy of the battery cell detection result is further improved.

In some embodiments, according to the voltage variation data of the to-be-measured battery cell in each frequency domain, obtaining a battery cell detection result of the to-be-measured battery cell includes: obtaining an initial detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in the first frequency domain; and under the condition that the initial detection result of the battery cell to be detected is abnormal, obtaining the battery cell detection result of the battery cell to be detected according to the initial detection result. If the initial detection result of the battery cell to be detected is abnormal, the battery cell to be detected has physical self-discharge, and the initial detection result can be directly used as the battery cell detection result of the battery cell to be detected at the moment without detecting voltage change data of other frequency domains, so that the detection efficiency of the battery cell to be detected is improved.

In some embodiments, according to the voltage variation data of the to-be-measured battery cell in each frequency domain, obtaining a battery cell detection result of the to-be-measured battery cell includes: obtaining an initial detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in the first frequency domain; and under the condition that the initial detection result of the battery cell to be detected is that the battery cell is normal, obtaining the battery cell detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in the second frequency domain.

In some embodiments, the obtaining the initial detection result of the to-be-detected battery cell according to the voltage variation data of the to-be-detected battery cell in the first frequency domain includes: and matching the voltage change data of the battery cell to be detected in the first frequency domain with the voltage change data of the normal battery cell in the first frequency domain or the voltage change data of the abnormal battery cell in the first frequency domain to obtain an initial detection result of the battery cell to be detected. The initial detection result of the battery cell to be detected is obtained by matching the voltage change data of the battery cell to be detected in the first frequency domain with at least one of the voltage change data of the normal battery cell in the first frequency domain or the voltage change data of the abnormal battery cell in the first frequency domain, so that the obtained initial detection result is more accurate.

In some embodiments, the obtaining the initial detection result of the to-be-detected battery cell according to the voltage variation data of the to-be-detected battery cell in the first frequency domain includes: obtaining a slope corresponding to the battery cell to be tested in the first frequency domain according to the voltage change data of the battery cell to be tested in the first frequency domain; and obtaining an initial detection result of the battery cell to be detected according to the slope. The slope corresponding to the battery cell to be tested in the first frequency domain is obtained through the voltage change data of the battery cell to be tested in the first frequency domain, so that the initial detection result of the battery cell to be tested is obtained by utilizing the slope corresponding to the battery cell to be tested in the first frequency domain, and whether the initial detection result of the battery cell to be tested is abnormal or not can be accurately judged, and the obtained initial detection result is more accurate.

In some embodiments, according to the voltage variation data of the to-be-measured battery cell in the second frequency domain, obtaining a battery cell detection result of the to-be-measured battery cell includes: and matching the voltage change data of the battery cell to be tested in the second frequency domain with the voltage change data of the normal battery cell in the second frequency domain or the voltage change data of the abnormal battery cell in the second frequency domain to obtain a battery cell detection result of the battery cell to be tested. The voltage change data of the battery cell to be tested in the second frequency domain is matched with at least one of the voltage change data of the normal battery cell in the second frequency domain or the voltage change data of the abnormal battery cell in the second frequency domain, so that a battery cell detection result of the battery cell to be tested is obtained, and the obtained battery cell detection result is more accurate.

In some embodiments, the voltage change data of the to-be-detected battery cell in at least one frequency domain is voltage change data amplified by a signal, so that the characteristics of the voltage change data finally used for detection are more obvious, and the accuracy of the obtained battery cell detection result of the to-be-detected battery cell is improved.

In a second aspect, the present application provides a battery cell detection device, including: the voltage data acquisition module is used for responding to a variable frequency excitation pulse signal applied to the battery cell to be tested to obtain voltage change data of the battery cell to be tested in each frequency domain; the detection result acquisition module is used for acquiring a battery cell detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in each frequency domain; the variable-frequency excitation pulse signals comprise a plurality of excitation pulse signals, wherein the variable-frequency excitation pulse signals have excitation pulse signal interval duration with different duration, and the excitation pulse signal interval duration is interval duration between adjacent excitation pulse signals.

According to the technical scheme, the current is applied to the battery cell to be tested, so that the battery cell detection result of the battery cell to be tested is determined according to the voltage change data of the battery cell to be tested, which is obtained by the applied excitation pulse signal. Therefore, the difference of the physical self-discharge process and the chemical self-discharge process in the time length of consuming the excitation pulse signal can be utilized to judge whether the voltage change data of the battery cell to be tested, to which the excitation pulse signal is applied, corresponds to the physical self-discharge process or the chemical self-discharge process, so that whether the battery cell to be tested is abnormal or not can be rapidly judged, the detection time length required for detecting the battery cell is reduced, meanwhile, the chemical self-discharge and the physical self-discharge of the battery cell can be effectively distinguished, and the accuracy of the battery cell detection result is improved.

In some embodiments, the voltage data acquisition module is specifically configured to: responding to a variable frequency excitation pulse signal applied to a battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in a first frequency domain and a second frequency domain; the interval duration of the excitation pulse signals of the first frequency domain and the second frequency domain is determined according to the chemical self-discharge duration required by the consumption of the excitation pulse signals of the normal battery core, and the interval duration of the excitation pulse signals of the second frequency domain is longer than the interval duration of the excitation pulse signals of the first frequency domain.

In some embodiments, the voltage data acquisition module is further to: determining the interval duration of the excitation pulse signals of the first frequency domain and the second frequency domain according to the chemical self-discharge duration required by the normal cell to consume the excitation pulse signals; the excitation pulse signal interval time length of the second frequency domain is longer than that of the first frequency domain.

In some embodiments, the excitation pulse signal interval duration of the first frequency domain is less than the chemical self-discharge duration required by the normal cell to consume the excitation pulse signal, and the excitation pulse signal interval duration of the second frequency domain is greater than or equal to the chemical self-discharge duration.

In some embodiments, the excitation pulse signal interval duration of the first frequency domain is not less than the physical self-discharge duration.

In some embodiments, the excitation pulse signal interval time of the variable frequency excitation pulse signal is greater than or equal to the physical self-discharge time period required by the abnormal cell to consume the excitation pulse signal.

In some embodiments, the detection result obtaining module is specifically configured to: obtaining an initial detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in the first frequency domain; and under the condition that the initial detection result of the battery cell to be detected is abnormal, obtaining the battery cell detection result of the battery cell to be detected according to the initial detection result.

In some embodiments, the detection result obtaining module is specifically configured to: obtaining an initial detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in the first frequency domain; and under the condition that the initial detection result of the battery cell to be detected is that the battery cell is normal, obtaining the battery cell detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in the second frequency domain.

In some embodiments, the detection result obtaining module is specifically configured to: and matching the voltage change data of the battery cell to be detected in the first frequency domain with the voltage change data of the normal battery cell in the first frequency domain or the voltage change data of the abnormal battery cell in the first frequency domain to obtain an initial detection result of the battery cell to be detected.

In some embodiments, the detection result obtaining module is specifically configured to: obtaining a slope corresponding to the battery cell to be tested in the first frequency domain according to the voltage change data of the battery cell to be tested in the first frequency domain; and obtaining an initial detection result of the battery cell to be detected according to the slope.

In some embodiments, the detection result obtaining module is specifically configured to: and matching the voltage change data of the battery cell to be tested in the second frequency domain with the voltage change data of the normal battery cell in the second frequency domain or the voltage change data of the abnormal battery cell in the second frequency domain to obtain a battery cell detection result of the battery cell to be tested.

In some embodiments, the voltage change data of the to-be-measured battery cell in at least one frequency domain is voltage change data amplified by a signal.

In a third aspect, the application provides an electronic device comprising a memory storing a computer program and a processor executing the method in an implementation of the first aspect when the processor executes the computer program.

In a fourth aspect, the present application provides a computer readable storage medium having stored thereon a computer program which when executed by a processor performs the method in an implementation of the first aspect.

In a fifth aspect, the present application provides a computer program product which, when run on a computer, causes the computer to perform the method of any of the alternative implementations of the first aspect, the first aspect or any of the alternative implementations of the third aspect, the third aspect.

The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the accompanying drawings. In the drawings:

FIG. 1 is a first flowchart of a method for detecting a battery cell according to some embodiments of the present application;

FIG. 2 is a schematic diagram of a variable frequency excitation pulse signal according to some embodiments of the present application;

FIG. 3 is a schematic diagram illustrating a cell reaction process according to some embodiments of the application;

FIG. 4 is a second flowchart of a method of battery cell detection according to some embodiments of the present application;

FIG. 5 is a third flowchart of a method of battery cell detection according to some embodiments of the present application;

fig. 6 is a schematic structural diagram of a battery cell detection device according to some embodiments of the present application;

fig. 7 is a schematic structural diagram of an electronic device according to some embodiments of the present application.

Reference numerals in the specific embodiments are as follows:

400-a voltage data acquisition module; 401-a detection result acquisition module; 500-an electronic device; 501-a processor; 502-memory; 503-communication bus.

Detailed Description

Embodiments of the technical scheme of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical aspects of the present application, and thus are merely examples, and are not intended to limit the scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description of the application and the claims and the description of the drawings above are intended to cover a non-exclusive inclusion.

In the description of embodiments of the present application, the technical terms "first," "second," and the like are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is merely an association relationship describing an association object, and indicates that three relationships may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" means two or more (including two), and similarly, "plural sets" means two or more (including two), and "plural sheets" means two or more (including two).

After the battery is assembled, the battery cells of the battery are usually required to be detected to screen out some battery cells with abnormal battery cells. If the battery cells are screened out, abnormal conditions such as SEI film forming abnormality and the like caused by lithium precipitation and black spots, pole piece wrinkling, pole ear cracking, water content or oil-water foreign matters are generated. Currently, for detecting a battery cell of a battery, an ac impedance of the battery cell is generally calculated, so as to determine whether the battery cell is abnormal according to a calculation result of the ac impedance.

However, when the ac impedance method is used to determine whether the power core is abnormal, an electrochemical workstation with high cost is required, and the ac module has high definition, so that it is difficult to achieve a precise state in a mass production environment state. Meanwhile, the winding structure of the battery cell can influence the high-frequency alternating current inductance, so that the battery cell detection mode has high detection cost and is easy to cause misjudgment of the battery cell detection result.

In view of the above technical problems, embodiments of the present application provide a method for detecting a battery cell, where voltage change data of a to-be-detected battery cell, to which a variable frequency excitation pulse signal is applied, in each frequency domain is obtained, so that characteristics of differences between voltage change data of a normal battery cell in each frequency domain and voltage change data of an abnormal battery cell in each frequency domain are utilized, and whether the to-be-detected battery cell is abnormal or not is judged by the voltage change data of the to-be-detected battery cell in each frequency domain, thereby reducing detection cost required for detecting the battery cell, reducing influence of a battery cell structure on a battery cell detection result, and improving accuracy of the battery cell detection result. The normal battery cell is a battery cell with a normal battery cell detection result, and the abnormal battery cell is a battery cell with an abnormal battery cell detection result.

The battery cell detection method, the device, the electronic equipment and the storage medium disclosed by the embodiment of the application can be applied to a controller and are used for realizing the abnormality detection of the battery cell. The controller comprises a server, wherein the server can be an independent server or a server cluster formed by a plurality of servers, and can also be a cloud server for providing cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDNs, basic cloud computing services such as big data and artificial intelligent sampling point equipment and the like.

According to some embodiments of the present application, a battery cell detection method according to an embodiment of the present application may be applied to the foregoing server. As shown in fig. 1, the battery cell detection method includes:

s101, responding to a variable frequency excitation pulse signal applied to a battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in each frequency domain;

s102, obtaining a battery cell detection result of the battery cell to be detected according to voltage change data of the battery cell to be detected in each frequency domain;

the variable-frequency excitation pulse signals comprise a plurality of excitation pulse signals, wherein the variable-frequency excitation pulse signals have excitation pulse signal interval duration with different duration, and the excitation pulse signal interval duration is interval duration between adjacent excitation pulse signals.

In some embodiments, the controller may be connected to a power source for outputting a variable frequency excitation pulse signal to control the power source to apply the variable frequency excitation pulse signal to the cell under test. The variable-frequency excitation pulse signal comprises a plurality of excitation pulse signals, the excitation pulse signals can be pulse currents, such as direct current pulse currents, and the interval duration of the excitation pulse signals between adjacent excitation pulse signals can be changed. As shown in fig. 2. The duration of the excitation pulse signal interval of adjacent excitation pulse signals, i.e. the pulse rest time, may exhibit an increasing trend, such as 125ms-250ms-375ms-500ms-625ms. The size of the excitation pulse signal can be set according to practical situations, for example, the size of the excitation pulse signal can be 20-200 mu A.

Under the condition that a variable frequency excitation pulse signal is applied to the battery cell to be tested, the overall voltage change data of the battery cell to be tested along with time, such as a time-voltage curve, can be obtained. And then dividing the overall voltage change data of the battery cell to be tested along with time according to each frequency domain of the variable frequency excitation pulse signal, and obtaining the voltage change data of each frequency domain.

In some embodiments, after obtaining the voltage change data of the to-be-measured battery cell in each frequency domain, the voltage change data of the to-be-measured battery cell in any frequency domain can be compared with the voltage change data obtained when the normal/abnormal battery cell applies the excitation pulse signal in the frequency domain, so as to determine whether the voltage change data of the to-be-measured battery cell in the frequency domain is abnormal. For example, if the similarity between the voltage change data of the to-be-measured cell in the frequency domain and the voltage change data obtained when the excitation pulse signal of the normal cell in the frequency domain is applied is greater than a preset value, such as 90%, it can be determined that the voltage change data of the to-be-measured cell in the frequency domain is normal; otherwise, determining that the voltage change data of the battery cell to be tested in the frequency domain is abnormal. Or if the similarity between the voltage change data of the battery cell to be tested in the frequency domain and the voltage change data obtained when the excitation pulse signal of the abnormal battery cell in the frequency domain is applied is greater than a preset value, such as 90%, determining that the voltage change data of the battery cell to be tested in the frequency domain is abnormal; otherwise, determining that the voltage change data of the battery cell to be tested in the frequency domain is normal.

If the voltage change data of the battery cell to be tested in each frequency domain are normal, the battery cell detection result of the battery cell to be tested can be determined to be normal; if the voltage change data of the battery cell to be tested in at least one frequency domain is abnormal, the battery cell detection result of the battery cell to be tested can be determined to be abnormal.

According to the battery cell detection method, the frequency conversion excitation pulse signals are applied to the battery cell to be detected, so that the battery cell detection result of the battery cell to be detected is determined according to the voltage change data of the battery cell to be detected in each frequency domain, which is obtained by the applied frequency conversion excitation pulse signals. Therefore, the characteristic that the voltage change data of the normal battery cell in each frequency domain is different from the voltage change data of the abnormal battery cell in each frequency domain can be utilized, whether the battery cell to be detected is abnormal or not is judged through the voltage change data of the battery cell to be detected in each frequency domain, the detection cost required by detecting the battery cell is reduced, the influence of the battery cell structure on the battery cell detection result is reduced, and the accuracy of the battery cell detection result is improved.

In order to more accurately determine whether the battery cell to be tested is abnormal, in some embodiments, according to an excitation pulse signal applied to the battery cell to be tested, voltage change data of the battery cell to be tested is obtained, including:

And responding to the variable frequency excitation pulse signal applied to the battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in the first frequency domain and the second frequency domain.

In some embodiments, if the cell has physical self-discharge, the cell performs an electron transfer process, i.e., a physical self-discharge process, then performs an ion transfer process, and finally performs a charge transfer process when an excitation pulse signal is applied to the cell, as shown in fig. 3. Since the physical self-discharge is performed during the electron transfer process, the reaction time is very fast, and the reaction time of the ion transfer process and the charge transfer process is slower than that of the electron transfer process, the frequency domain of the variable frequency excitation pulse signal can be divided into a first frequency domain with a high pulse frequency and a second frequency domain with a medium-low pulse frequency according to the reaction time. Therefore, the voltage change data of the first frequency domain can be used for detecting whether an electron transmission process exists, and the voltage change data of the second frequency domain can be used for detecting whether an ion transmission process and a charge transfer process are abnormal, so that abnormal positioning is realized.

To enable more accurate anomaly localization, in some embodiments, it further comprises: determining the interval duration of the excitation pulse signals of the first frequency domain and the second frequency domain according to the chemical self-discharge duration required by the normal cell to consume the excitation pulse signals; the excitation pulse signal interval time length of the second frequency domain is longer than that of the first frequency domain.

Under the condition that the control power supply converts the frequency excitation pulse signals to the to-be-detected battery core, because the physical self-discharge and chemical self-discharge consume different time periods of the excitation pulse signals, the interval time period of the excitation pulse signals of the first frequency domain can be determined according to the chemical self-discharge time period required by the normal battery core consuming the excitation pulse signals, so that two adjacent excitation pulse signals with the interval time period smaller than or equal to the interval time period of the excitation pulse signals of the first frequency domain are divided into the first frequency domain. In this way, under the condition that variable frequency excitation pulse signals are sequentially applied to the battery core to be tested, if the battery core to be tested is abnormal, the change trend of the voltage change data of the battery core to be tested in the first frequency domain is obviously different from that of the battery core to be tested in the first frequency domain under normal conditions; if the battery cell to be tested is normal, the change trend of the voltage change data of the battery cell to be tested in the first frequency domain is obviously different from that of the voltage change data of the battery cell to be tested in the first frequency domain under abnormal conditions. Meanwhile, any two adjacent excitation pulse signals with interval time length longer than that of the excitation pulse signals in the first frequency domain can be divided into a second frequency domain to correspond to an ion transmission process and a charge transfer process. Therefore, voltage change data of the battery cell to be tested in the first frequency domain and the second frequency domain can be obtained based on the excitation pulse signals in the first frequency domain and the second frequency domain.

Under the condition that variable frequency excitation pulse signals are sequentially applied to the battery cells to be tested, the interval duration of the excitation pulse signals in the first frequency domain is determined according to at least one of the chemical self-discharge duration required by the consumption of the excitation pulse signals by the normal battery cells or the physical self-discharge duration required by the elimination of the excitation pulse signals by the abnormal battery cells, and the interval duration of the excitation pulse signals in the second frequency domain is longer than the interval duration of the excitation pulse signals in the first frequency domain, so that after the variable frequency excitation pulse signals are applied to the battery cells to be tested, the voltage change data of the battery cells to be tested in the first frequency domain corresponding to the electronic transmission process and the voltage change data of the battery cells to be tested in the second frequency domain corresponding to the ion transmission process and the charge transfer process can be obtained, and the abnormal location can be rapidly carried out by utilizing the frequency domain corresponding to the abnormality when the battery cells are determined to be abnormal in the follow-up.

In order to make the correspondence between the divided frequency domains and the cell reaction process more accurate, in some embodiments, the interval duration of the excitation pulse signal of the first frequency domain is smaller than the chemical self-discharge duration, and the interval duration of the excitation pulse signal of the second frequency domain is greater than or equal to the chemical self-discharge duration.

Because the interval duration of the excitation pulse signals in the first frequency domain is smaller than the chemical self-discharge duration, if the frequency conversion excitation pulse signals are applied to the battery core to be tested, if the battery core to be tested is normal, namely, only chemical self-discharge exists, and no electronic transmission process exists, the excitation pulse signals applied in the first frequency domain cannot be completely consumed, the charged excitation pulse signals can be accumulated, the overall voltage change of the battery core to be tested slowly rises, and therefore the voltage change data of the battery core to be tested can show rising trend. In this way, the chemical self-discharge duration is taken as a critical value, the interval duration of the excitation pulse signals of the first frequency domain is set to be smaller than the chemical self-discharge duration, and the interval duration of the excitation pulse signals of the first frequency domain is set to be larger than the chemical self-discharge duration, so that the first frequency domain corresponding to the electron transmission process and the second frequency domain corresponding to the ion transmission process and the charge transfer process are accurately divided, and the subsequent abnormal positioning is more accurate.

The chemical self-discharge duration may be determined by applying a single excitation pulse signal to the normal cell in advance, so as to obtain voltage change data of the normal cell. After the voltage change data of the normal battery cell is obtained, the time point of the initial voltage of the normal battery cell before the single excitation pulse signal is applied to the normal battery cell and the time point of the voltage of the normal battery cell falling back to the target voltage after the single excitation pulse signal is applied to the normal battery cell can be obtained from the voltage change data of the normal battery cell. The difference between the target voltage and the initial voltage is smaller than or equal to a preset value, and the preset value can be set according to actual conditions. For example, the difference between the target voltage and the initial voltage may be 0, that is, a point in time when the voltage of the normal cell drops back to the initial voltage after the single excitation pulse signal is applied to the normal cell is acquired. Then, according to the time interval between the two, the chemical self-discharge duration, namely the chemical self-discharge duration of the normal battery cell, can be determined. For example, the time interval between the two is taken as the chemical self-discharge duration. Or, the time interval between the two can be used as the chemical self-discharge duration corresponding to a single excitation pulse signal applied to a normal cell, and then the chemical self-discharge duration corresponding to a plurality of excitation pulse signals is subjected to operations such as linear regression or averaging, so that the chemical self-discharge duration can be obtained.

The voltage change data of the normal battery cell is obtained by applying an excitation pulse signal to the normal battery cell, so that the chemical self-discharge duration is determined according to the time interval between the initial voltage and the target voltage in the voltage change data of the normal battery cell, the obtained chemical self-discharge duration is more accurate, and the accuracy of the subsequently obtained battery cell detection result is further improved.

In some embodiments, the excitation pulse signal interval time of the variable frequency excitation pulse signal is longer than the physical self-discharge time period required for the abnormal cell to consume the excitation pulse signal. Because the interval duration of the excitation pulse signal of the variable frequency excitation pulse signal is not less than the duration required by the abnormal cell to consume the excitation pulse signal, if the cell to be tested is abnormal, namely physical self-discharge exists, the excitation pulse signal applied in the first frequency domain can be completely consumed, the voltage change of the whole cell to be tested is not obvious or is reduced, and therefore the voltage change data of the cell to be tested can show a stable or reduced trend. Therefore, after the interval duration of the excitation pulse signal of the variable frequency excitation pulse signal applied to the battery cell to be detected is set to be not less than the physical self-discharge duration required by the abnormal battery cell consumption excitation pulse signal, whether the battery cell to be detected is abnormal or not can be judged by judging whether the voltage change data of the battery cell to be detected in the first frequency domain is reduced or in a stable state under the condition that the fixed frequency excitation pulse signal is applied to the battery cell to be detected, and the accuracy of the battery cell detection result is further improved.

For determining the physical self-discharge duration, a single excitation pulse signal is applied to the abnormal battery cell in advance to obtain voltage change data of the abnormal battery cell. After the voltage change data of the abnormal battery cell is obtained, the time point of the initial voltage of the abnormal battery cell before the single excitation pulse signal is applied to the abnormal battery cell and the time point of the voltage of the abnormal battery cell falling back to the target voltage after the single excitation pulse signal is applied to the abnormal battery cell can be obtained from the voltage change data of the abnormal battery cell. For example, the difference between the target voltage and the initial voltage may be 0, that is, a point in time when the voltage of the abnormal cell drops back to the initial voltage after the single excitation pulse signal is applied to the abnormal cell is acquired. Then, according to the time interval between the two, the physical self-discharge time length, namely the physical self-discharge time length of the abnormal battery cell, can be determined. Such as the time interval between the two as the physical self-discharge duration. Or, the time interval between the two can be used as the physical self-discharge duration corresponding to the single excitation pulse signal applied to the abnormal battery cell, and then the physical self-discharge duration corresponding to the plurality of excitation pulse signals is subjected to operations such as linear regression or averaging, so that the physical self-discharge duration can be obtained.

The voltage change data of the abnormal battery cell is obtained by applying an excitation pulse signal to the abnormal battery cell, so that the physical self-discharge duration is determined according to the time interval between the initial voltage and the target voltage in the voltage change data of the abnormal battery cell, the obtained physical self-discharge duration is more accurate, and the accuracy of the subsequently obtained battery cell detection result is further improved.

In some embodiments, after obtaining the voltage change data of the to-be-measured battery cell in the first frequency domain and the second frequency domain, the battery cell detection result of the to-be-measured battery cell can be obtained according to the voltage change data of the first frequency domain and the second frequency domain.

In order to improve the detection efficiency of the to-be-detected battery cell, in some embodiments, as shown in fig. 4, according to the voltage change data of the to-be-detected battery cell in each frequency domain, a battery cell detection result of the to-be-detected battery cell is obtained, including:

s201, obtaining an initial detection result of the battery cell to be detected according to voltage change data of the battery cell to be detected in a first frequency domain;

s202, under the condition that the initial detection result of the battery cell to be detected is abnormal, obtaining the battery cell detection result of the battery cell to be detected according to the initial detection result.

In some embodiments, after the voltage change data of the to-be-measured battery cell in each frequency domain is obtained, the initial detection result of the to-be-measured battery cell may be determined by using the voltage change data of the to-be-measured battery cell in the first frequency domain.

Under the condition that the electric core is subjected to titration of the excitation pulse signal, the tiny electric quantity charged in the excitation pulse signal is consumed within a very short standing time after the excitation pulse signal is charged, so that the voltage change of the whole electric core is not obvious or reduced. If the cell has only chemical self-discharge, in the case of titration of the excitation pulse signal to the cell, the tiny electric quantity charged in the excitation pulse signal is not consumed in a very short standing time after the completion of the charging of the excitation pulse signal, so that the charged electric quantity can be accumulated, and the voltage variation of the whole cell is slowly increased. By utilizing the difference, the voltage change data of the battery cell to be tested in the first frequency domain can be used for determining the consumed time length of the excitation pulse signal applied to the battery cell to be tested, so as to judge whether the battery cell to be tested has physical self-discharge according to the time length, and further obtain the battery cell detection result of the battery cell to be tested.

As one possible implementation manner, the power supply may be used to apply the excitation pulse signal to at least one normal cell or at least one abnormal cell in advance, and the duration of the consumption of the excitation pulse signal by the normal cell may be recorded as a preset duration, or the duration of the consumption of the excitation pulse signal by the abnormal cell may be recorded as a preset duration. After the voltage change data of the battery cell to be measured in the first frequency domain is obtained, the time length required by the voltage of the battery cell to be measured to be restored to the initial voltage of the battery cell to be measured after the excitation pulse signal is applied can be obtained from the voltage change data, so that the time length is determined as the consumed time length of the excitation pulse signal. The initial voltage is the voltage measured before the excitation pulse signal is applied to the battery cell to be measured. Then, the consumed time period of the excitation pulse signal is compared with a preset time period. Under the condition that the preset time length is the time length of consuming the excitation pulse signal by the normal battery cell, if the time length consumed by the excitation pulse signal is smaller than the preset time length, determining that the voltage change data of the battery cell to be detected in the first frequency domain is abnormal, and determining that the initial detection result of the battery cell to be detected is abnormal; otherwise, determining that the voltage change data of the battery cell to be tested in the first frequency domain is normal, thereby determining that the initial detection result of the battery cell to be tested is that the battery cell is normal. Under the condition that the preset time length is the time length of the abnormal battery cell consuming the excitation pulse signal, if the time length consumed by the excitation pulse signal is longer than the preset time length, the initial detection result of the battery cell to be detected can be determined to be normal; otherwise, determining the initial detection result of the battery cell to be detected as abnormal battery cell.

If the initial detection result of the battery cell to be detected is abnormal, the battery cell to be detected has physical self-discharge, and the initial detection result can be directly used as the battery cell detection result of the battery cell to be detected at the moment without detecting voltage change data of other frequency domains, so that the detection efficiency of the battery cell to be detected is improved.

In order to improve accuracy of the initial detection result, in some embodiments, after the voltage change data of the to-be-detected battery cell in the first frequency domain is obtained, the voltage change data of the to-be-detected battery cell in the first frequency domain may be matched with at least one of the voltage change data of the normal battery cell in the first frequency domain or the voltage change data of the abnormal battery cell in the first frequency domain, so as to obtain a battery cell detection result of the to-be-detected battery cell.

As a possible implementation manner, the voltage change data of the to-be-measured battery cell in the first frequency domain may be subjected to similarity matching with the voltage change data of the normal battery cell in the first frequency domain, for example, the voltage-time curve of the to-be-measured battery cell in the first frequency domain is subjected to similarity matching with the voltage-time curve of the normal battery cell in the first frequency domain, so as to obtain the similarity of the voltage change data of the to-be-measured battery cell in the first frequency domain and the voltage change data of the normal battery cell in the first frequency domain. If the similarity of the voltage change data of the battery cell to be tested in the first frequency domain and the voltage change data of the normal battery cell in the first frequency domain reaches the preset similarity, such as 90%, determining that the initial detection result of the battery cell to be tested is normal; otherwise, the initial detection result of the to-be-detected battery cell can be determined to be abnormal. The preset similarity can be set according to actual conditions.

Similarly, the voltage change data of the battery cell to be tested in the first frequency domain can be subjected to similarity matching with the voltage change data of the abnormal battery cell in the first frequency domain. If the similarity of the voltage change data of the battery cell to be tested in the first frequency domain and the voltage change data of the abnormal battery cell in the first frequency domain reaches the preset similarity, such as 90%, determining that the initial detection result of the battery cell to be tested is abnormal; otherwise, the initial detection result of the to-be-detected battery cell can be determined to be normal.

As another possible implementation manner, the voltage change data of the battery cell to be tested in the first frequency domain may be subjected to similarity matching with the voltage change data of the normal battery cell in the first frequency domain, so as to obtain the similarity between the voltage change data of the battery cell to be tested in the first frequency domain and the voltage change data of the normal battery cell in the first frequency domain, as the first similarity. And performing similarity matching on the voltage change data of the battery cell to be tested in the first frequency domain and the voltage change data of the abnormal battery cell in the first frequency domain to obtain second similarity of the voltage change data of the battery cell to be tested in the first frequency domain and the voltage change data of the abnormal battery cell in the first frequency domain. Then comparing the first similarity with the second similarity; if the first similarity is greater than the second similarity, determining that the initial detection result of the to-be-detected battery cell is normal; otherwise, the initial detection result of the to-be-detected battery cell can be determined to be abnormal.

The initial detection result of the battery cell to be detected is obtained by matching the voltage change data of the battery cell to be detected in the first frequency domain with at least one of the voltage change data of the normal battery cell in the first frequency domain or the voltage change data of the abnormal battery cell in the first frequency domain, so that the obtained initial detection result is more accurate.

In addition to determining an initial detection result of the to-be-detected cell by comparing voltage change data of the to-be-detected cell in the first frequency domain with voltage change data of the normal/abnormal cell in the first frequency domain, in some embodiments, obtaining the initial detection result of the to-be-detected cell according to the voltage change data of the to-be-detected cell in the first frequency domain includes: according to the voltage change data of the battery cell to be measured in the first frequency domain, obtaining the corresponding slope of the battery cell to be measured in the first frequency domain; and obtaining an initial detection result of the battery cell to be detected according to the slope.

The speed of the physical self-discharge consumption excitation pulse signal is greatly higher than that of the chemical self-discharge consumption excitation pulse signal, so that the voltage change data obtained after the excitation pulse signal of the first frequency domain is applied to the normal cell, the slope of the voltage change data is greatly different from the voltage change data obtained after the excitation pulse signal of the first frequency domain is applied to the abnormal cell, namely the voltage change data of the normal cell in the first frequency domain is larger than that of the voltage change data of the abnormal cell in the first frequency domain. Therefore, after the voltage change data of the battery cell to be measured in the first frequency domain is obtained, the slope corresponding to the battery cell to be measured in the first frequency domain can be calculated according to the voltage change data of the battery cell to be measured in the first frequency domain, so that the initial detection result of the battery cell to be measured can be determined based on the slope corresponding to the battery cell to be measured in the first frequency domain.

As a possible implementation manner, the slope corresponding to the first frequency domain of the battery cell to be tested may be compared with the slope corresponding to the first frequency domain of the normal/abnormal battery cell to determine the initial detection result of the battery cell to be tested. If the difference between the slope corresponding to the first frequency domain of the battery cell to be tested and the slope corresponding to the first frequency domain of the normal battery cell is smaller than the preset threshold, the initial detection result of the battery cell to be tested is determined to be normal. Or if the slope corresponding to the first frequency domain of the battery cell to be detected and the difference value between the slope corresponding to the first frequency domain of the abnormal battery cell are smaller than the preset threshold value, determining that the initial detection result of the battery cell to be detected is abnormal. Or, obtaining the slope corresponding to the first frequency domain of the battery cell to be tested, taking the difference value between the slope corresponding to the first frequency domain of the battery cell to be tested and the slope corresponding to the first frequency domain of the normal battery cell as a first difference value, and obtaining the slope corresponding to the first frequency domain of the battery cell to be tested, and taking the difference value between the slope corresponding to the first frequency domain of the abnormal battery cell as a second difference value. If the first difference value is smaller than the second difference value, determining that the initial detection result of the battery cell to be detected is normal; otherwise, determining that the initial detection result of the battery cell to be detected is abnormal.

As another possible embodiment, since there is an abnormal cell of the physical self-discharge, the voltage change of the whole is not obvious or reduced under the condition of applying the excitation pulse signal of the first frequency domain, that is, the slope of the voltage change data of the abnormal cell in the first frequency domain is generally smaller than 0. Therefore, after the slope corresponding to the battery cell to be measured in the first frequency domain is obtained through calculation according to the voltage change data of the battery cell to be measured in the first frequency domain, whether the slope is smaller than 0 can be directly judged. If the slope is smaller than 0, the initial detection result of the cell to be detected can be determined to be abnormal.

The slope corresponding to the battery cell to be tested in the first frequency domain is obtained through the voltage change data of the battery cell to be tested in the first frequency domain, so that the initial detection result of the battery cell to be tested is obtained by utilizing the slope corresponding to the battery cell to be tested in the first frequency domain, and whether the initial detection result of the battery cell to be tested is abnormal or not can be accurately judged, and the obtained initial detection result is more accurate.

In some embodiments, as shown in fig. 5, according to voltage change data of the to-be-measured battery cell in each frequency domain, a battery cell detection result of the to-be-measured battery cell is obtained, including:

s301, obtaining an initial detection result of the battery cell to be detected according to voltage change data of the battery cell to be detected in a first frequency domain;

S302, under the condition that the initial detection result of the battery cell to be detected is that the battery cell is normal, the battery cell detection result of the battery cell to be detected is obtained according to the voltage change data of the battery cell to be detected in the second frequency domain.

In some embodiments, if the initial detection result of the to-be-detected battery cell is that the battery cell is normal, it indicates that there is no physical self-discharge of the to-be-detected battery cell, and at this time, it may be determined whether the to-be-detected battery cell is abnormal by detecting voltage variation data of the second frequency domain. Wherein the second frequency domain may include a first sub-frequency domain corresponding to a response time of the ion transport process and a second sub-frequency domain corresponding to a response time of the charge transfer process. Under the condition that the initial detection result of the battery cell to be detected is that the battery cell is normal, whether the battery cell to be detected is abnormal or not can be judged by detecting the voltage change data of the first sub-frequency domain. If the battery cell to be detected is abnormal according to the voltage change data of the first sub-frequency domain, the condition that the ion transmission process of the battery cell to be detected is abnormal is indicated, and the battery cell to be detected is not required to be detected. If the to-be-measured battery cell is determined to be normal according to the voltage change data of the first sub-frequency domain, the ion transmission process of the to-be-measured battery cell is indicated to be normal, and then the detection result of the to-be-measured battery cell in the charge conversion process is obtained by detecting the voltage change data of the second sub-frequency domain, so that the detection result is used as the final battery cell detection result of the to-be-measured battery cell.

In order to improve accuracy of the cell detection result, in some embodiments, according to voltage change data of the cell to be detected in the second frequency domain, obtaining the cell detection result of the cell to be detected includes: and matching the voltage change data of the battery cell to be tested in the second frequency domain with the voltage change data of the normal battery cell in the second frequency domain or the voltage change data of the abnormal battery cell in the second frequency domain to obtain a battery cell detection result of the battery cell to be tested.

As a possible implementation manner, the voltage change data of the to-be-measured battery cell in the second frequency domain may be subjected to similarity matching with the voltage change data of the normal battery cell in the second frequency domain, for example, the voltage-time curve of the to-be-measured battery cell in the second frequency domain is subjected to similarity matching with the voltage-time curve of the normal battery cell in the second frequency domain, so as to obtain the similarity of the voltage change data of the to-be-measured battery cell in the second frequency domain and the voltage change data of the normal battery cell in the second frequency domain. If the similarity of the voltage change data of the battery cell to be tested in the second frequency domain and the voltage change data of the normal battery cell in the second frequency domain reaches the preset similarity, for example, 90%, determining that the battery cell detection result of the battery cell to be tested is normal; otherwise, the cell detection result of the cell to be detected can be determined to be abnormal. The preset similarity can be set according to actual conditions.

Similarly, the voltage change data of the battery cell to be tested in the second frequency domain can be subjected to similarity matching with the voltage change data of the abnormal battery cell in the second frequency domain. If the similarity of the voltage change data of the battery cell to be tested in the second frequency domain and the voltage change data of the abnormal battery cell in the second frequency domain reaches the preset similarity, for example, 90%, determining that the battery cell detection result of the battery cell to be tested is abnormal; otherwise, the cell detection result of the cell to be detected can be determined to be normal.

As another possible implementation manner, the similarity matching can be performed on the voltage variation data of the to-be-tested battery cell in the second frequency domain and the voltage variation data of the normal battery cell in the second frequency domain, so as to obtain the similarity of the voltage variation data of the to-be-tested battery cell in the second frequency domain and the voltage variation data of the normal battery cell in the second frequency domain, and the similarity is used as the first similarity. And performing similarity matching on the voltage change data of the battery cell to be tested in the second frequency domain and the voltage change data of the abnormal battery cell in the second frequency domain to obtain second similarity of the voltage change data of the battery cell to be tested in the second frequency domain and the voltage change data of the abnormal battery cell in the second frequency domain. Then comparing the first similarity with the second similarity; if the first similarity is greater than the second similarity, determining that the cell detection result of the cell to be detected is normal; otherwise, the cell detection result of the cell to be detected can be determined to be abnormal.

The voltage change data of the battery cell to be tested in the second frequency domain is matched with at least one of the voltage change data of the normal battery cell in the second frequency domain or the voltage change data of the abnormal battery cell in the second frequency domain, so that a battery cell detection result of the battery cell to be tested is obtained, and the obtained battery cell detection result is more accurate.

In order to further improve the accuracy of the obtained cell detection result of the to-be-detected cell, in some embodiments, the voltage change data of the to-be-detected cell in at least one frequency domain is voltage change data amplified by a signal. For example, since the voltage change data of the normal battery cell and the abnormal battery cell in the second frequency domain tend to be the same and both show a descending or stable trend, the signal amplification can be performed on the voltage change data of the battery cell to be detected in the second frequency domain through windowed fourier transform or wavelet transform, so that the characteristics of the voltage change data finally used for detection are more obvious, and the accuracy of the obtained battery cell detection result of the battery cell to be detected is improved.

In order to reduce the interference of noise in the voltage change data on the cell detection result, after the voltage change data of the cell to be detected in each frequency domain is obtained, linear regression processing can be performed on the voltage change data corresponding to any frequency domain by using a least square method for the voltage change data corresponding to the frequency domain, so that each voltage data with larger noise is screened from the voltage change data corresponding to the frequency domain. And screening out voltage data with a distance from the coordinate point to the target straight line being greater than a preset distance from the voltage change data corresponding to the first frequency domain under a two-dimensional coordinate system formed by voltage and time. The target straight line is generated after linear regression processing is performed on voltage change data corresponding to the first frequency domain. And screening out the voltage data with the distance from the coordinate point to the target straight line being greater than the preset distance from the voltage change data corresponding to the first frequency domain, so as to obtain the target voltage change data corresponding to the first frequency domain.

After the target voltage change data corresponding to any frequency domain is obtained, the detection result of the battery cell to be detected in the frequency domain can be obtained by utilizing the similarity between the target voltage change data and the voltage change data of the normal/abnormal battery cell in the frequency domain, so that the influence of noise in the voltage change data of the battery cell to be detected on the battery cell detection result is reduced, and the accuracy of the obtained battery cell detection result is improved.

Fig. 6 shows a schematic structural diagram of a battery cell detection device according to the present application, and it should be understood that the device corresponds to the embodiment of the method performed in fig. 1, 4 and 5, and is capable of performing the steps involved in the foregoing method, and specific functions of the device may be referred to in the foregoing description, and detailed descriptions thereof are omitted herein as appropriate to avoid redundancy. The device includes at least one software functional module that can be stored in memory in the form of software or firmware (firmware) or cured in an Operating System (OS) of the device. Specifically, the device comprises: the voltage data acquisition module 400 is configured to respond to a variable frequency excitation pulse signal applied to the to-be-measured battery cell, and obtain voltage variation data of the to-be-measured battery cell in each frequency domain; the detection result obtaining module 401 is configured to obtain a cell detection result of the to-be-detected cell according to voltage change data of the to-be-detected cell in each frequency domain; the variable-frequency excitation pulse signals comprise a plurality of excitation pulse signals, wherein the variable-frequency excitation pulse signals have excitation pulse signal interval duration with different duration, and the excitation pulse signal interval duration is interval duration between adjacent excitation pulse signals.

According to the technical scheme, the electric core detection result of the electric core to be detected is determined by applying the variable frequency excitation pulse signal to the electric core to be detected so as to obtain the voltage change data of the electric core to be detected in each frequency domain according to the applied variable frequency excitation pulse signal. Therefore, the characteristic that the voltage change data of the normal battery cell in each frequency domain is different from the voltage change data of the abnormal battery cell in each frequency domain can be utilized, whether the battery cell to be detected is abnormal or not is judged through the voltage change data of the battery cell to be detected in each frequency domain, the detection cost required by detecting the battery cell is reduced, the influence of the battery cell structure on the battery cell detection result is reduced, and the accuracy of the battery cell detection result is improved.

According to some embodiments of the application, the voltage data acquisition module 400 is specifically configured to: and responding to the variable frequency excitation pulse signal applied to the battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in the first frequency domain and the second frequency domain.

According to some embodiments of the application, the voltage data acquisition module 400 is further configured to: determining the interval duration of the excitation pulse signals of the first frequency domain and the second frequency domain according to the chemical self-discharge duration required by the consumption of the excitation pulse signals of the normal battery cell; the excitation pulse signal interval time length of the second frequency domain is longer than that of the first frequency domain.

According to some embodiments of the application, the first frequency domain excitation pulse signal interval duration is less than the chemical self-discharge duration, and the second frequency domain excitation pulse signal interval duration is greater than the chemical self-discharge duration.

According to some embodiments of the application, the excitation pulse signal interval time of the variable frequency excitation pulse signal is greater than or equal to the physical self-discharge time required for the abnormal cell to consume the excitation pulse signal.

According to some embodiments of the present application, the detection result obtaining module 401 is specifically configured to: according to the voltage change data of the battery cell to be tested in the first frequency domain, obtaining an initial detection result of the battery cell to be tested; and under the condition that the initial detection result of the battery cell to be detected is abnormal, obtaining the battery cell detection result of the battery cell to be detected according to the initial detection result.

According to some embodiments of the present application, the detection result obtaining module 401 is specifically configured to: according to the voltage change data of the battery cell to be tested in the first frequency domain, obtaining an initial detection result of the battery cell to be tested; and under the condition that the initial detection result of the battery cell to be detected is that the battery cell is normal, obtaining the battery cell detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in the second frequency domain.

According to some embodiments of the present application, the detection result obtaining module 401 is specifically configured to: and matching the voltage change data of the battery cell to be detected in the first frequency domain with the voltage change data of the normal battery cell in the first frequency domain or the voltage change data of the abnormal battery cell in the first frequency domain to obtain an initial detection result of the battery cell to be detected.

According to some embodiments of the present application, the detection result obtaining module 401 is specifically configured to: according to the voltage change data of the battery cell to be measured in the first frequency domain, obtaining the corresponding slope of the battery cell to be measured in the first frequency domain; and obtaining an initial detection result of the battery cell to be detected according to the slope.

According to some embodiments of the present application, the detection result obtaining module 401 is specifically configured to: and matching the voltage change data of the battery cell to be tested in the second frequency domain with the voltage change data of the normal battery cell in the second frequency domain or the voltage change data of the abnormal battery cell in the second frequency domain to obtain a battery cell detection result of the battery cell to be tested.

According to some embodiments of the application, the voltage change data of the cell to be tested in at least one frequency domain is the voltage change data amplified by the signal.

According to some embodiments of the present application, as shown in fig. 7, the present application provides an electronic device 500, including: processor 501 and memory 502, the processor 501 and memory 502 being interconnected and in communication with each other by a communication bus 503 and/or other form of connection mechanism (not shown), the memory 502 storing a computer program executable by the processor 501, the processor 501 executing the computer program when the computing device is running to perform the method performed by the external machine in any alternative implementation, such as: responding to a variable frequency excitation pulse signal applied to the battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in each frequency domain; according to the voltage change data of the battery cell to be tested in each frequency domain, obtaining a battery cell detection result of the battery cell to be tested; the variable-frequency excitation pulse signals comprise a plurality of excitation pulse signals, wherein the variable-frequency excitation pulse signals have excitation pulse signal interval duration with different duration, and the excitation pulse signal interval duration is interval duration between adjacent excitation pulse signals.

The present application provides a computer readable storage medium having stored thereon a computer program which when executed by a processor performs a method according to any of the preceding alternative implementations.

The storage medium may be implemented by any type of volatile or nonvolatile Memory device or combination thereof, such as static random access Memory (Static Random Access Memory, SRAM), electrically erasable Programmable Read-Only Memory (Electrically Erasable Programmable Read-Only Memory, EEPROM), erasable Programmable Read-Only Memory (Erasable Programmable Read Only Memory, EPROM), programmable Read-Only Memory (PROM), read-Only Memory (ROM), magnetic Memory, flash Memory, magnetic disk, or optical disk.

The present application provides a computer program product which, when run on a computer, causes the computer to perform the method in any of the alternative implementations.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application, and are intended to be included within the scope of the appended claims and description. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims

1. A method for detecting a battery cell, the method comprising:

responding to a variable frequency excitation pulse signal applied to a battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in each frequency domain;

obtaining a battery cell detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in each frequency domain;

2. The method of claim 1, wherein obtaining voltage change data of the cell under test according to an excitation pulse signal applied to the cell under test comprises:

and responding to the variable frequency excitation pulse signal applied to the battery cell to be tested, and obtaining voltage change data of the battery cell to be tested in a first frequency domain and a second frequency domain.

3. The method of claim 2, wherein the method further comprises:

determining the interval duration of the excitation pulse signals of the first frequency domain and the second frequency domain according to the chemical self-discharge duration required by the normal cell to consume the excitation pulse signals;

The excitation pulse signal interval time length of the second frequency domain is longer than that of the first frequency domain.

4. A method according to claim 2 or 3, wherein the excitation pulse signal interval duration of the first frequency domain is less than the chemical self-discharge duration required for a normal cell to consume the excitation pulse signal, and the excitation pulse signal interval duration of the second frequency domain is greater than or equal to the chemical self-discharge duration.

5. A method according to any one of claims 1 to 3, wherein the excitation pulse signal interval time of the variable frequency excitation pulse signal is greater than or equal to the physical self-discharge time period required for the abnormal cell to consume the excitation pulse signal.

6. The method according to claim 2, wherein obtaining the cell detection result of the cell to be detected according to the voltage change data of the cell to be detected in each frequency domain comprises:

obtaining an initial detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in the first frequency domain;

and under the condition that the initial detection result of the battery cell to be detected is abnormal, obtaining the battery cell detection result of the battery cell to be detected according to the initial detection result.

7. The method according to claim 2, wherein obtaining the cell detection result of the cell to be detected according to the voltage change data of the cell to be detected in each frequency domain comprises:

and under the condition that the initial detection result of the battery cell to be detected is that the battery cell is normal, obtaining the battery cell detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in the second frequency domain.

8. The method according to claim 6 or 7, wherein the obtaining the initial detection result of the to-be-detected cell according to the voltage variation data of the to-be-detected cell in the first frequency domain includes:

and matching the voltage change data of the battery cell to be detected in the first frequency domain with the voltage change data of the normal battery cell in the first frequency domain or the voltage change data of the abnormal battery cell in the first frequency domain to obtain an initial detection result of the battery cell to be detected.

9. The method according to claim 6 or 7, wherein the obtaining the initial detection result of the to-be-detected cell according to the voltage variation data of the to-be-detected cell in the first frequency domain includes:

Obtaining a slope corresponding to the battery cell to be tested in the first frequency domain according to the voltage change data of the battery cell to be tested in the first frequency domain;

and obtaining an initial detection result of the battery cell to be detected according to the slope.

10. The method of claim 7, wherein obtaining the cell detection result of the cell to be detected according to the voltage change data of the cell to be detected in the second frequency domain comprises:

and matching the voltage change data of the battery cell to be tested in the second frequency domain with the voltage change data of the normal battery cell in the second frequency domain or the voltage change data of the abnormal battery cell in the second frequency domain to obtain a battery cell detection result of the battery cell to be tested.

11. The method of claim 1, 2, 3, 6, 7 or 10, wherein the voltage change data of the cell under test in at least one frequency domain is signal amplified voltage change data.

12. A battery cell detection device, the device comprising:

the voltage data acquisition module is used for responding to a variable frequency excitation pulse signal applied to the battery cell to be tested to obtain voltage change data of the battery cell to be tested in each frequency domain;

The detection result acquisition module is used for acquiring a battery cell detection result of the battery cell to be detected according to the voltage change data of the battery cell to be detected in each frequency domain;

13. An electronic device comprising a processor and a memory storing a computer program, characterized in that the processor implements the method of any one of claims 1 to 11 when executing the computer program.

14. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the method of any one of claims 1 to 11.