Method for measuring internal resistance and self-discharge rate of battery through battery impedance chip

Abstract

The invention discloses a method for measuring the internal resistance and the self-discharge rate of a battery through a battery impedance chip. The method comprises the steps that S1, the battery is connected with the impedance chip; s2, initializing the system; s3, applying an excitation signal; s4, signal acquisition; s5, internal resistance calculation; s6, calculating the self-discharge rate; and S7, data analysis and storage. According to the method, rapid and accurate measurement of the internal resistance of the battery is realized, so that an effective technical means is provided for real-time evaluation of the health state of the battery.

Description

Technical Field

[0001] The present invention relates to a battery health monitoring technology, and in particular to a method for measuring the internal resistance and self-discharge rate of a battery by using a battery impedance chip. Background Art

[0002] With the development of energy storage technology, batteries, as core components of energy conversion and storage, have been widely used in portable electronic devices, electric vehicles, energy storage systems and other fields. The performance and life of batteries are directly related to the reliability and economy of the entire system. Battery internal resistance and self-discharge rate are two key parameters for evaluating battery performance and health status. They are of great significance to battery operating efficiency, thermal management, and prediction of battery life.

[0003] However, existing methods for measuring battery internal resistance and self-discharge rate have some limitations. Traditional measurement methods usually rely on voltage drop tests, which require the battery to be discharged or charged for a short period of time. This method is not only time-consuming, but also causes additional stress on the battery.

[0004] In addition, existing measurement technologies often lack sufficient accuracy and real-time performance to meet the needs of modern battery management systems for efficient and accurate monitoring. In complex application scenarios, such as large-scale battery energy storage systems or battery packs for electric vehicles, real-time and accurate monitoring of battery performance is particularly important.

[0005] Therefore, developing a fast and accurate method to measure battery internal resistance and self-discharge rate has significant practical application value for improving battery efficiency, ensuring battery safe operation, and optimizing battery maintenance strategies.

[0006] The present invention is to solve the above-mentioned problems in the prior art and provides a method for measuring the internal resistance and self-discharge rate of a battery through a battery impedance chip. The method realizes fast and accurate measurement of the internal resistance of the battery, thereby providing an effective technical means for real-time evaluation of the battery health status. Summary of the invention

[0007] The purpose of the embodiment of the present application is to provide a method for measuring the internal resistance and self-discharge rate of a battery by using a battery internal resistance chip, which method has the characteristics of simple operation, fast measurement and accurate results.

[0008] To achieve the above-mentioned purpose, the present invention provides a method for measuring the internal resistance and self-discharge rate of a battery through a battery impedance chip, comprising: S1, connecting the battery to the impedance chip; S2, initializing the system; S3, applying an excitation signal; S4, signal acquisition; S5, calculating the internal resistance; S6, measuring the self-discharge rate; S7, analyzing and storing data.

[0009] Further optionally, the connection between the battery and the impedance chip includes: connecting the positive and negative electrodes of the battery to the corresponding interfaces of the battery impedance chip through wires to ensure stable electrical connection. The positive electrode of the battery is connected to the VCC port (positive power supply) of the battery impedance chip through a wire; the negative electrode of the battery is connected to the GND port (ground wire) of the battery impedance chip through a wire.

[0010] Further optionally, the system is initialized, including: S201, after the system is started, the battery impedance chip executes a power-on self-test program to detect the integrity and functionality of the internal circuit of the chip; S202, ensuring that the communication link between the battery impedance chip and the external control device and the data acquisition card has been established and calibrated.

[0011] Further optionally, the application of the excitation signal includes: S301, excitation signal generation: selecting a suitable excitation signal type, setting parameters such as frequency, amplitude and duration of the excitation signal, and optimizing the parameters according to the battery type and measurement requirements; S302, signal amplification: if the amplitude of the excitation signal is small, the signal needs to be amplified by a signal amplifier to ensure that the battery can generate a measured response; S303, signal application: applying the excitation signal to both ends of the battery through precise electrical connection; at the same time, ensuring that the application of the signal is synchronized with the data acquisition card to facilitate accurate capture of the battery response.

[0012] Further optionally, the signal acquisition includes: S401, voltage acquisition: acquiring the voltage response signal at both ends of the battery through a data acquisition card; S402, current acquisition: using a current sensor to acquire the current response signal flowing through the battery.

[0013] Further optionally, the internal resistance calculation includes: calculating the equivalent internal resistance of the battery using Ohm's law method according to the collected voltage and current response data.

[0014] Further optionally, the self-discharge rate measurement includes: under no-load conditions, recording the voltage drop of the battery within a certain time interval (such as 24 hours), and calculating the self-discharge rate according to the rated capacity of the battery.

[0015] Further optionally, the data analysis and storage include: S701, screening effective signals in the original data, removing noise in the signal through a filter, and then using the statistical method of standard deviation to set a threshold for the data, and data exceeding the normal range is regarded as an outlier and excluded. The screened data is normalized and scaled to a uniform magnitude to ensure that the data follows a consistent format and unit for easy analysis; S702, the screened data is subjected to frequency domain analysis using a fast Fourier transform (FFT) to extract features that are helpful for battery health status assessment. Such as internal resistance, self-discharge rate, charge and discharge curve, etc.; S703, establishing machine learning technology, using the data as input to the machine learning model, and using a random forest model to classify the battery health status. Parameters are tuned by cross-validation evaluation model and grid search. To analyze data and predict battery performance; S704, the battery health status and remaining life are evaluated based on the analysis results, and key features such as the internal resistance growth rate and the fluctuation range of the self-discharge rate are extracted from the battery internal resistance and self-discharge rate data. Then a battery health status evaluation model is established to predict the battery health status through the key features of the battery. At the same time, a remaining life prediction model based on historical data is created to estimate the expected service life of the battery; S705, design the database, determine the type of data that needs to be stored and the user's needs for data retrieval, update, etc., and then design the conceptual model and logical model of the database, which includes the battery information table, measurement data table and health status table. Then design the security of the database, including access control and data encryption, and finally formulate a database backup plan. After the database is formulated, the battery test data and analysis results will be stored in the database.

[0016] The above technical solution has the following beneficial effects:

[0017] It can be seen from the above embodiments that the present application adopts a battery impedance chip to measure the battery internal resistance and self-discharge rate to monitor the battery internal resistance and self-discharge rate. This method can accurately calculate the data of the battery internal resistance and self-discharge rate, thereby overcoming the current complex testing equipment, cumbersome operating steps and inaccurate measurement results, thereby achieving the effect of accurately measuring the battery internal resistance and self-discharge rate while achieving simple operation.

[0018] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A schematic diagram of a method for measuring battery internal resistance and self-discharge rate by using a battery impedance chip provided by an embodiment of the present invention;

[0021] Figure 2 A flow chart for measuring the internal resistance and self-discharge rate of a battery by using a battery impedance chip provided in an embodiment of the present invention;

[0022] Figure 3 A schematic diagram of the connection of a battery impedance chip provided by an embodiment of the present invention;

[0023] Figure 4 is a flow chart of applying an excitation signal provided by an embodiment of the present invention;

[0024] Figure 5 is a signal acquisition flow chart provided by an embodiment of the present invention;

[0025] Figure 6 is a data analysis and storage flow chart provided by an embodiment of the present invention;

[0026] Figure 7 It is a system initialization flow chart provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In order to solve the problems of insufficient accuracy and complicated operation steps in the prior art for measuring the internal resistance and self-discharge rate of a battery, an embodiment of the present invention provides a method for measuring the internal resistance and self-discharge rate of a battery by using a battery impedance chip. Figure 1 A schematic diagram of a battery impedance chip connection provided by an embodiment of the present invention. Figure 2 The internal resistance and self-discharge rate measurement flow chart provided in the embodiment of the present invention is as follows: Figure 1 , Figure 2 As shown, the method includes:

[0029] S1, the battery is connected to the impedance chip;

[0030] Connect the positive and negative electrodes of the battery to the corresponding interfaces of the battery impedance chip through wires to ensure stable electrical connection. The positive electrode of the battery is connected to the VCC port (positive power supply) of the battery impedance chip through a wire; the negative electrode of the battery is connected to the GND port (ground wire) of the battery impedance chip through a wire.

[0031] S2, system initialization;

[0032] After the system is started, the battery impedance chip executes a power-on self-test procedure to detect the integrity and functionality of the chip's internal circuits; at the same time, it ensures that the communication link between the battery impedance chip and the external control device and data acquisition card has been established and calibrated.

[0033] S3, applying excitation signal;

[0034] Excitation signal generation: select the appropriate excitation signal type, set the excitation signal parameters such as frequency, amplitude and duration, and optimize the parameters according to the battery type and measurement requirements; signal amplification: if the amplitude of the excitation signal is small, the signal needs to be amplified by a signal amplifier to ensure that the battery can produce a measured response; signal application: apply the excitation signal to both ends of the battery through precise electrical connections; at the same time, ensure that the signal application is synchronized with the data acquisition card to accurately capture the battery's response.

[0035] S4, signal acquisition;

[0036] Voltage acquisition: The voltage response signal at both ends of the battery is collected through a data acquisition card; Current acquisition: The current response signal flowing through the battery is collected using a current sensor.

[0037] S5, internal resistance calculation;

[0038] Based on the collected voltage and current response data, the equivalent internal resistance of the battery is calculated using Ohm's law and frequency domain analysis method.

[0039] The formula is as follows:

[0040]

[0041] In the formula, R eq : Battery equivalent internal resistance, unit is Ω; V rms It is the effective value (RMS, Root Mean Square) of the voltage response across the battery, in V; I rms It is the effective value of the current response, in A.

[0042] S6, self-discharge rate measurement;

[0043] Under no-load conditions, record the voltage drop of the battery within a certain time interval (such as 24 hours) and calculate the self-discharge rate based on the rated capacity of the battery.

[0044] The formula is as follows:

[0045]

[0046] Where, SDR: self-discharge rate of the battery; ΔV is the drop in battery voltage within time t, in V; V 0 is the initial voltage of the battery, in V; t is the time for self-discharge rate measurement, in h.

[0047] S7, data analysis and storage;

[0048] Filter valid signals from the original data, exclude noise or outliers, and convert the filtered data into a format suitable for analysis, such as time series or frequency domain data; extract features that are helpful for evaluating the battery health status from the filtered data, such as internal resistance, self-discharge rate, charge and discharge curves, etc.; perform machine learning on the data, analyze the data and predict battery performance, and perform repeatable tests to verify the repeatability and stability of the analysis process; evaluate the battery health status and remaining life based on the analysis results; design a database and store the battery test data and analysis results in the database.

[0049] As an optional implementation, Figure 3 A schematic diagram of a battery impedance chip connection provided by an embodiment of the present invention, such as Figure 3 As shown, the battery impedance chip connections include:

[0050] Connect the positive and negative electrodes of the battery to the corresponding interfaces of the battery impedance chip through wires to ensure stable electrical connection. The positive electrode of the battery is connected to the VCC port (positive power supply) of the battery impedance chip through a wire; the negative electrode of the battery is connected to the GND port (ground wire) of the battery impedance chip through a wire.

[0051] As an optional implementation, Figure 4 The excitation signal application flow chart provided in the embodiment of the present invention is as follows: Figure 4 As shown, including:

[0052] S301, excitation signal generation: select a suitable excitation signal type, set the excitation signal parameters such as frequency, amplitude and duration, and optimize the parameters according to the battery type and measurement requirements;

[0053] S302, signal amplification: if the amplitude of the excitation signal is small, the signal needs to be amplified by a signal amplifier to ensure that the battery can generate a measured response;

[0054] S303, signal application: apply the excitation signal to both ends of the battery through precise electrical connection; ensure that the signal application is synchronized with the data acquisition card to accurately capture the response of the battery.

[0055] As an optional implementation, Figure 5 The signal acquisition flow chart provided by the embodiment of the present invention is as follows: Figure 5 As shown, the battery signal is collected and estimated, including:

[0056] S401, voltage acquisition: collecting voltage response signals at both ends of the battery through a data acquisition card;

[0057] S402, current collection: using a current sensor to collect a current response signal flowing through the battery.

[0058] As an optional implementation, Figure 6 The data analysis and storage flow chart provided by the embodiment of the present invention is as follows: Figure 6 The figure shows the process of data analysis and storage, including:

[0059] S701. Filter valid signals from the original data, remove noise from the signals through filters, and then use the statistical method of standard deviation to set a threshold for the data. Data that exceeds the normal range is considered as an outlier and excluded. Normalize the filtered data and scale it to a uniform magnitude to ensure that the data follows a consistent format and unit for easy analysis;

[0060] S702, using fast Fourier transform (FFT) to perform frequency domain analysis on the filtered data to extract features that are helpful for evaluating the battery health status, such as internal resistance, self-discharge rate, charge and discharge curves, etc.;

[0061] S703. Establish machine learning technology, use data as input to machine learning models, and use random forest models to classify battery health status. Use cross-validation evaluation models and grid search to perform parameter tuning to analyze data and predict battery performance.

[0062] S704. Evaluate the health status and remaining life of the battery based on the analysis results, and extract key features from the battery internal resistance and self-discharge rate data, such as the internal resistance growth rate and the fluctuation range of the self-discharge rate. Then establish a battery health status evaluation model to predict the battery health status based on the key characteristics of the battery. At the same time, create a remaining life prediction model based on historical data to estimate the expected service life of the battery;

[0063] S705. Design the database, determine the type of data to be stored and the user's needs for data retrieval and update, and then design the conceptual model and logical model of the database, which includes the battery information table, measurement data table, and health status table. Then design the security of the database, including access control and data encryption, and finally formulate a database backup plan. After the database is formulated, the battery test data and analysis results will be stored in the database.

[0064] As an optional implementation, Figure 7 A system initialization flow chart provided by an embodiment of the present invention, such as Figure 7 As shown, the system initialization process is shown, including:

[0065] S201, after the system is started, the battery impedance chip executes a power-on self-test program to detect the integrity and functionality of the chip's internal circuit;

[0066] S202, ensuring that the communication link between the battery impedance chip and the external control device and the data acquisition card has been established and calibrated.

[0067] The above technical solution has the following beneficial effects:

[0068] The present application uses a battery impedance chip to measure the internal resistance and self-discharge rate of the battery. This method can accurately calculate the data of the battery's internal resistance and self-discharge rate, thereby overcoming the current complex testing equipment, cumbersome operating steps and inaccurate measurement results, thereby achieving the effect of accurately measuring the battery's internal resistance and self-discharge rate while achieving simple operation.

[0069] Those skilled in the art will readily appreciate other embodiments of the present application after considering the description and practicing the contents disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The description and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the claims.

[0070] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for measuring battery internal resistance and self-discharge rate by using a battery impedance chip, characterized in that: include: S1, the battery is connected to the impedance chip; S2, system initialization; S3, applying excitation signal; S4, signal acquisition; S5, internal resistance calculation; S6, self-discharge rate calculation; S7. Data analysis and storage.

2. The method for measuring battery internal resistance and self-discharge rate by using a battery impedance chip according to claim 1, characterized in that: The battery is connected to the impedance chip, including: Connect the positive and negative electrodes of the battery to the corresponding interfaces of the battery impedance chip through wires to ensure stable electrical connection. The positive electrode of the battery is connected to the VCC port (positive power supply) of the battery impedance chip through a wire; the negative electrode of the battery is connected to the GND port (ground wire) of the battery impedance chip through a wire.

3. The method for measuring battery internal resistance and self-discharge rate by using a battery impedance chip according to claim 1, characterized in that: System initialization, including: S201, after the system is started, the battery impedance chip executes a power-on self-test program to detect the integrity and functionality of the chip's internal circuit; S202, ensuring that the communication link between the battery impedance chip and the external control device and the data acquisition card has been established and calibrated.

4. The method for measuring battery internal resistance and self-discharge rate by using a battery impedance chip according to claim 1, characterized in that: Stimulus signal application, including: S301, excitation signal generation: select a suitable excitation signal type, set the excitation signal parameters such as frequency, amplitude and duration, and optimize the parameters according to the battery type and measurement requirements; S302, signal amplification: if the amplitude of the excitation signal is small, it is necessary to amplify the signal through a signal amplifier to ensure that the battery can generate a measured response; S303, signal application: apply the excitation signal to both ends of the battery through precise electrical connection; at the same time, ensure that the signal application is synchronized with the data acquisition card to accurately capture the response of the battery.

5. The method for measuring battery internal resistance and self-discharge rate by using a battery impedance chip according to claim 1, characterized in that: Signal acquisition, including: S401, voltage acquisition: collecting voltage response signals at both ends of the battery through a data acquisition card; S402, current collection: using a current sensor to collect a current response signal flowing through the battery.

6. The method for measuring battery internal resistance and self-discharge rate by using a battery impedance chip according to claim 1, characterized in that: Internal resistance calculation, including: Based on the collected voltage and current response data, the equivalent internal resistance of the battery is calculated using the Ohm's law method. Among them, the calculation formula for internal resistance is: In the formula, R eq : Battery equivalent internal resistance, unit is Ω; V rms It is the effective value (RMS, Root Mean Square) of the voltage response across the battery, in V; I rms It is the effective value of the current response, in A.

7. The method for measuring battery internal resistance and self-discharge rate by using a battery impedance chip according to claim 1, characterized in that: Self-discharge rate calculation, including: Under no-load conditions, record the voltage drop of the battery within a certain time interval (such as 24 hours), and calculate the self-discharge rate based on the rated capacity of the battery. Among them, the calculation formula for self-discharge rate is: Where, SDR: self-discharge rate of the battery; ΔV is the drop in battery voltage within time t, in V; V0 is the initial voltage of the battery, in V; t is the time for measuring the self-discharge rate, in h.

8. The method for measuring battery internal resistance and self-discharge rate by using a battery impedance chip according to claim 1, characterized in that: Data analysis and storage, including: S701. Filter valid signals from the original data, remove noise from the signals through filters, and then use the statistical method of standard deviation to set a threshold for the data. Data that exceeds the normal range is considered as an outlier and excluded. Normalize the filtered data and scale it to a uniform magnitude to ensure that the data follows a consistent format and unit for easy analysis; S702, using fast Fourier transform (FFT) to perform frequency domain analysis on the filtered data to extract features that are helpful for evaluating the battery health status, such as internal resistance, self-discharge rate, charge and discharge curves, etc.; S703. Establish machine learning technology, use data as input to machine learning models, and use random forest models to classify battery health status. Use cross-validation evaluation models and grid search to perform parameter tuning to analyze data and predict battery performance. S704. Evaluate the health status and remaining life of the battery based on the analysis results, and extract key features from the battery internal resistance and self-discharge rate data, such as the internal resistance growth rate and the fluctuation range of the self-discharge rate. Then establish a battery health status evaluation model to predict the battery health status based on the key characteristics of the battery. At the same time, create a remaining life prediction model based on historical data to estimate the expected service life of the battery; S705. Design the database, determine the type of data to be stored and the user's needs for data retrieval and update, and then design the conceptual model and logical model of the database, which includes the battery information table, measurement data table, and health status table. Then design the security of the database, including access control and data encryption, and finally formulate a database backup plan. After the database is formulated, the battery test data and analysis results will be stored in the database.

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