CN216560929U - Battery active regulation and control device based on active external excitation - Google Patents

Abstract

The utility model relates to a battery active regulation and control device based on active external excitation. The device consists of a pulse excitation source, a sample to be tested and an electrochemical impedance spectrometer, wherein the high-speed pulse excitation source applies external pulse excitation to the sample (battery) to be tested to regulate and control the internal running state of the battery; and (3) carrying out low-frequency sweep frequency impedance analysis on the sample to be detected by the electrochemical impedance spectrometer to obtain the frequency response of the sample to be detected and represent the external regulation and control effect of the battery. The utility model provides a device for actively regulating and controlling the reaction process in a battery by adopting an external excitation source, which can regulate and control according to the capacitance effect of an original electric appliance, keep the safety and reliability of a battery system under the condition of not adding other battery equalization equipment and a power electronic circuit, and has great practical value for designing, operating and maintaining the battery system.

Description

Battery active regulation and control device based on active external excitation

Technical Field

The utility model belongs to the field of electrical engineering, and particularly relates to a battery active regulation and control device based on active external excitation.

Background

In the existing battery design, operation and maintenance processes, which typically view batteries as completely passive power devices, the existing paradigm determines that it is difficult to assess the battery state once the battery is put into use. Thus, the passive battery design, operation and maintenance paradigm results in the safety and maintenance costs of the battery generally being higher than the design costs of the battery. The battery active regulation and control device based on the active external excitation provided by the utility model utilizes the ubiquitous electric capacitance effect in the battery for the first time, identifies the battery state on line through the electric capacitance effect, regulates and controls the internal behavior of the battery in an active external excitation mode, and provides a novel practical operation device for the safe, efficient and intelligent application of the battery.

SUMMERY OF THE UTILITY MODEL

The utility model relates to a device for regulating and controlling the electrochemical process in a battery by utilizing the electric capacitance effect and an external excitation method.

The theoretical basis of the utility model is the inventive electric capacitance effect. A capacitor, which is composed of two conductors and a dielectric material sandwiched between them, is a container for charge storage. In the battery, the positive and negative plates are conductive media, and the vulcanized layer is made of dielectric materials. Thus, the vulcanized battery can be regarded as a capacitor, which is referred to as a capacitive effect in the present invention. The capacitance effect generally exists in the life cycles of various batteries, and the utility model adopts the electric capacitance effect to react the battery interface change condition and the electrochemical process, thereby providing mechanism support for the proposed external regulation and control device.

The utility model provides a battery active regulation and control device based on active external excitation, which consists of a pulse excitation source, a sample to be tested, an electrochemical impedance spectrometer and a frequency response analyzer, wherein: the output end of the pulse excitation source is connected with the input end of a sample to be detected, the output end of the sample to be detected is connected with the input end of an electrochemical impedance spectrometer, the output end of the electrochemical impedance spectrometer is connected with the input end of a frequency response analyzer, and the pulse excitation source applies external pulse excitation to the sample to be detected to regulate and control the internal running state of the sample to be detected; and performing low-frequency sweep frequency impedance analysis on the sample to be detected by the electrochemical impedance spectrometer to obtain the frequency response of the sample to be detected, and representing the external regulation and control effect of the sample to be detected by the frequency response analyzer.

In the utility model, the sample to be detected is a battery.

In the utility model, the pulse excitation source adopts a high-speed pulse excitation source.

According to the utility model, an electrochemical impedance spectrometer is used for measuring the frequency response of a sample to be measured under low frequency, a Nyquist curve is drawn, the lowest impedance point on the curve is used as a battery resonance point, and the moving range of the battery resonance point is used as the representation of the electrochemical regulation and control process in the battery.

The utility model realizes the electrochemical regulation and control of the battery without adding other battery balancing equipment and power electronic circuits.

The utility model has the beneficial effects that: the utility model utilizes the common electric capacitance effect in the battery and adopts external excitation to regulate and control the electrochemical process in the battery, so that the regulation and control process of the battery is changed from passive to active, the safety and the reliability of a battery system are kept under the condition of not adding other battery equalization equipment and a power electronic circuit, and a reliable and effective device is provided for designing, operating and maintaining the battery system.

Drawings

Fig. 1 is a schematic structural diagram of an active battery regulation device based on active external excitation adopted in the utility model;

FIG. 2 is a schematic illustration of the electrical capacitance effect utilized by the present invention;

FIG. 3 is a schematic diagram of battery frequency response before and after regulation based on external excitation;

FIG. 4 is a flow chart of the operation of an active regulation device for a battery based on active external excitation;

reference numbers in the figures: 1 is a pulse excitation source, 2 is a sample to be detected, 3 is an electrochemical impedance spectrometer, and 4 is a frequency response analyzer.

Detailed Description

The utility model is further illustrated by the following examples in conjunction with the accompanying drawings.

Example 1: as shown in fig. 1, the active battery regulation device based on active external excitation is composed of four main parts, namely a high-speed pulse excitation source 1, a sample (battery) 2 to be measured, an electrochemical impedance spectrometer 3 and a frequency response analyzer 4. The model of the high-speed pulse excitation source 1 is NF BP4610, the model of the electrochemical impedance spectrometer 3 is BIOLOGIC VMP3, and the RSA306 is adopted by the frequency response analyzer 4. After initializing the amplitude and frequency parameters of the high-speed pulsed excitation source 1, the excitation is applied to the battery. The time for applying the stimulus is typically 2 hours. After the pulse is applied, the battery conditioning effect of the external stimulus is derived by the frequency response analyzer 4 based on the electric capacitance effect shown in fig. 2. Fig. 3 is an example of frequency response analysis. Fig. 4 is a flow chart of the operation of the battery active regulation device based on active external excitation.

The method comprises the following specific steps:

(1) according to the innovative electric capacitance effect provided by the utility model, the positive plate and the negative plate of the sample 2 (battery) to be measured are conductive media, and the vulcanized layer is made of dielectric materials, so that the sample 1 (battery) to be measured is regarded as a capacitor;

(2) the active battery regulation and control device based on active external excitation adopts a high-speed pulse excitation source 1 to carry out battery excitation. The amplitude and frequency parameters of the pulsed excitation may be initialized or changed as desired to obtain different frequency responses. The waveform of the excitation is a narrow square wave signal with a duty cycle below 5% and an amplitude in the range of 0.1C A to 1C A, where C is the rated capacity of the battery. The frequency range of the excitation is 1kHz to 100 kHz;

(3) the active battery regulation and control device based on active external excitation evaluates the electrochemical process in the battery by testing the frequency response of the battery. Specifically, an electrochemical impedance spectroscopy technology is selected for measuring the frequency response. The complex impedance of the battery is measured by taking a sine wave with the amplitude of 5mV and the frequency of 10mHz to 1MHz as a disturbance source. Each measurement was averaged over a logarithmic frequency range of 10mHz to 1MHz at 6 points and tested 2 times per perturbation step. The final frequency response result is the average value of the measured complex impedance;

(4) the frequency response estimation as described in step (3) is performed by plotting the nyquist curve of the impedance. And drawing by taking the real number component of the complex impedance as a horizontal axis and the imaginary number component of the complex impedance as a vertical axis to obtain a Nyquist curve. The lowest point of the impedance is observed on the Nyquist curve, and the lowest point is the resonance point of the battery. The resonance point of the battery moves after external excitation is applied, and the electrochemical process in the battery is evaluated according to the frequency range of the movement of the resonance point;

(5) and (5) properly adjusting the parameter setting of the external high-speed pulse excitation source according to the evaluation result in the step (4), and repeating the steps (2) to (5) until the regulation result or the repetition times meet the requirements.

The present embodiment is illustrated with one measured data point: the battery capacity is 6 Ah; external excitation current 2A, excitation waveform is square wave, duty ratio is 5%, excitation frequency is 20kHz, and excitation time is 1 h; measuring frequency response by using an electrochemical impedance spectroscopy technology; the complex impedance of the battery is measured by taking a sine wave with the amplitude of 10mV and the frequency of 10mHz to 1MHz as a disturbance source. Each measurement was averaged over a logarithmic frequency range of 10mHz to 1mHz at 12 points and tested 2 times per perturbation step. The final frequency response result is the average of the measured complex impedances.

Before excitation, as shown by the triangular dashed line in fig. 3, the frequency at the lowest point of the frequency response is 9.7kHz, corresponding to a slowing of the electrochemical process inside the cell. After excitation, as in the diamond-shaped line of fig. 3, the frequency at the lowest point of the frequency response is 11.2kHz, which corresponds to a faster electrochemical process inside the cell.

Claims (2)

1. The utility model provides a battery initiative regulation and control device based on initiative external excitation, by pulse excitation source, the sample that awaits measuring, electrochemistry impedance spectrometer and frequency response analysis appearance constitute which characterized in that: the output end of the pulse excitation source is connected with the input end of a sample to be detected, the output end of the sample to be detected is connected with the input end of an electrochemical impedance spectrometer, the output end of the electrochemical impedance spectrometer is connected with the input end of a frequency response analyzer, and the pulse excitation source applies external pulse excitation to the sample to be detected to regulate and control the internal running state of the sample to be detected; and performing low-frequency sweep frequency impedance analysis on the sample to be detected by the electrochemical impedance spectrometer to obtain the frequency response of the sample to be detected, and representing the external regulation and control effect of the sample to be detected by the frequency response analyzer.

2. The active battery regulation device based on active external excitation according to claim 1, wherein: the sample to be detected is a battery.

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