Electrochemical impedance spectroscopy measurement method, excitation signal generation method and device

Abstract

The embodiment of the present invention provides an electrochemical impedance spectrum measurement method, an excitation signal generation method and a device. By performing PID control on the difference between the actual sampling signal of the measurement loop where the electrochemical system is located and the reference sinusoidal signal, the output control signal is introduced into the above-mentioned measurement loop as an excitation signal, so that the actual sampling signal of the measurement loop gradually matches the reference sinusoidal signal, which is equivalent to applying a sinusoidal AC excitation signal to the electrochemical system to be measured, and the corresponding response signal is also an AC signal. The electrochemical impedance of the electrochemical system can be calculated according to the AC response signal; and then the electrochemical impedance spectrum of the electrochemical system can be obtained according to the response signal corresponding to the excitation signal of different frequencies. Based on the embodiment of the present invention, the electrochemical impedance spectrum measurement is performed without the need for an AC signal generator, which can reduce the measurement cost and the size of the measurement equipment, and can be conveniently and quickly applied to the impedance spectrum measurement of electrochemical systems in various scenarios.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to an electrochemical impedance spectrum measurement method, an excitation signal generation method and a device. Background Art

[0002] Electrochemical Impedance Spectroscopy (EIS) is an important technology for studying electrochemical systems and is widely used in the fields of batteries, electrochemical materials, etc. Its principle is to apply small-amplitude AC excitation signals of different frequencies to the electrochemical system, measure the response signal of the electrochemical system caused by the excitation signal, and calculate the electrochemical impedance of the electrochemical system at different frequencies based on the response signal and the excitation signal, that is, the electrochemical impedance spectrum. The internal structure and operating status of the electrochemical system can be analyzed based on the electrochemical impedance spectrum. For example, when applied in the field of battery technology, the battery failure can be judged and the battery life can be predicted by analyzing the electrochemical impedance spectrum of the battery. Therefore, electrochemical impedance spectroscopy measurement equipment has become an essential laboratory equipment in related fields.

[0003] However, measuring electrochemical impedance spectroscopy often requires an AC signal generator to generate an AC excitation signal. Due to the large size and high cost of the AC signal generator, electrochemical impedance spectroscopy measurements can usually only be performed in laboratories and are difficult to be widely used in the production and use of electrochemical systems such as batteries. Summary of the invention

[0004] In view of the above technical problems, embodiments of the present invention provide an electrochemical impedance spectroscopy measurement method, an excitation signal generation method and a device.

[0005] In a first aspect, an embodiment of the present invention provides an electrochemical impedance spectroscopy measurement method, comprising:

[0006] Acquire an actual sampling signal of a measurement circuit where the electrochemical system is located; the actual sampling signal includes any one of a current signal and a voltage signal;

[0007] Acquire a reference sinusoidal signal, and modulate the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm to obtain an excitation signal;

[0008] inputting the excitation signal into the measurement circuit;

[0009] Acquiring a response signal of the measurement loop;

[0010] The electrochemical impedance of the electrochemical system is calculated based on the response signal.

[0011] In a second aspect, an embodiment of the present invention provides a method for generating an excitation signal, comprising:

[0012] Acquire an actual sampling signal of a target circuit; the actual sampling signal includes any one of a current signal and a voltage signal of the target circuit;

[0013] A reference sinusoidal signal is obtained, and a difference between the actual sampling signal and the reference sinusoidal signal is modulated according to a PID control algorithm to obtain an excitation signal, and the excitation signal is input into the target loop.

[0014] In a third aspect, an embodiment of the present invention provides an electrochemical impedance spectroscopy measuring device, comprising:

[0015] A first acquisition module is used to acquire an actual sampling signal of a measurement circuit where the electrochemical system is located; the actual sampling signal includes any one of a current signal and a voltage signal;

[0016] An algorithm control module, used for obtaining a reference sinusoidal signal, modulating the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm, and obtaining an excitation signal;

[0017] A signal output module, used for inputting the excitation signal into the measurement loop;

[0018] A second acquisition module, used to acquire a response signal of the measurement loop;

[0019] The impedance analysis module is used to calculate the electrochemical impedance of the electrochemical system according to the response signal.

[0020] In a fourth aspect, an embodiment of the present invention provides an electrochemical impedance spectroscopy measuring device, comprising:

[0021] An auxiliary circuit unit is connected to the electrochemical system to be measured and forms a measurement loop with the electrochemical system;

[0022] A signal measuring unit, used for collecting the signal of the measuring loop;

[0023] The core processing unit is connected to the auxiliary circuit unit and the signal measurement unit, and is used to obtain an actual sampling signal of a measurement circuit where an electrochemical system is located through the signal measurement unit, wherein the actual sampling signal includes any one of a current signal and a voltage signal; obtain a reference sinusoidal signal, modulate the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm, and obtain an excitation signal; input the excitation signal into the measurement circuit; obtain a response signal of the measurement circuit through the signal measurement unit, and calculate the electrochemical impedance of the electrochemical system according to the response signal.

[0024] In a fifth aspect, an embodiment of the present invention provides an excitation signal generating device, including:

[0025] A first acquisition module, configured to acquire an actual sampling signal of a target loop; the actual sampling signal includes any one of a current signal and a voltage signal of the target loop;

[0026] An algorithm control module, used for obtaining a reference sinusoidal signal, modulating the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm, and obtaining an excitation signal;

[0027] A signal output module is used to input the excitation signal into the target loop.

[0028] In a sixth aspect, an embodiment of the present invention provides an electronic device, including:

[0029] A memory for storing a computer program product;

[0030] The processor is used to execute the computer program product stored in the memory, and when the computer program product is executed, the method described in the first aspect or the second aspect is implemented.

[0031] In the seventh aspect, an embodiment of the present invention provides a computer-readable storage medium, characterized in that computer program instructions are stored on the computer-readable storage medium, and when the computer program instructions are executed, the method described in the first aspect or the second aspect above is implemented.

[0032] In summary, the electrochemical impedance spectrum measurement method, excitation signal generation method and related devices and equipment provided by the embodiments of the present invention perform PID control on the difference between the actual sampling signal and the reference sinusoidal signal of the measurement loop where the electrochemical system is located, and introduce the output control signal as the excitation signal into the above-mentioned measurement loop, so that the actual sampling signal of the measurement loop gradually matches the reference sinusoidal signal, which is equivalent to applying a sinusoidal AC excitation signal to the electrochemical system to be measured, and the corresponding response signal is also an AC signal. The electrochemical impedance of the electrochemical system can be calculated according to the AC response signal; and then the electrochemical impedance spectrum of the electrochemical system can be obtained according to the response signal corresponding to the excitation signal of different frequencies. Based on the embodiment of the present invention, the electrochemical impedance spectrum measurement does not require an AC signal generator, which can reduce the measurement cost and the size of the measurement equipment, and can be conveniently and quickly applied to the impedance spectrum measurement of electrochemical systems in various scenarios. At the same time, since the above-mentioned measurement circuit is connected in parallel with the working circuit of the electrochemical system, it will not affect the operating condition of its working circuit, and there is no need to disconnect the electrochemical system from its working circuit. Therefore, the embodiment of the present invention can realize the measurement of its electrochemical impedance spectrum under the normal operating conditions of the electrochemical system, that is, during the production and use of the electrochemical system, its electrochemical impedance spectrum can be measured at any time based on the embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic diagram of an application scenario provided by an embodiment of the present invention;

[0034] Figure 2 A flow chart of an electrochemical impedance spectroscopy measurement method provided in an embodiment of the present invention;

[0035] Figure 3 A schematic diagram of generating an excitation signal based on PID control provided in an embodiment of the present invention;

[0036] Figure 4 A schematic diagram of a measurement circuit for measuring electrochemical impedance spectroscopy provided in an embodiment of the present invention;

[0037] Figure 5 A flowchart of a method for generating an excitation signal provided by an embodiment of the present invention;

[0038] Figure 6 A structural block diagram of an electrochemical impedance spectroscopy measuring device provided in an embodiment of the present invention;

[0039] Figure 7 A structural block diagram of an excitation signal generating device provided by an embodiment of the present invention;

[0040] Figure 8 A structural block diagram of an electrochemical impedance spectroscopy measurement device provided in an embodiment of the present invention;

[0041] Fig. 9 for Figure 8 A schematic diagram of a structure of the device shown is implemented based on an integrated circuit board;

[0042] Fig.10 A structural block diagram of an electronic device provided by an embodiment of the present invention;

[0043] Fig.11 A schematic diagram of the relationship between sample data of a reference sinusoidal signal and a sampling time interval provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The present application is further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present application will become clearer and more specific.

[0045] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0046] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0047] In order to solve the problem that the existing electrochemical impedance spectroscopy measurement equipment generates AC excitation signals based on AC signal generators, resulting in large equipment volume and high cost, the embodiments of the present invention provide a low-cost, convenient and fast electrochemical impedance spectroscopy measurement method, excitation signal generation method and device. The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0048] For ease of understanding, the technical terms involved in the embodiments of the present invention are first introduced here. The PID control algorithm, namely the proportional, integral and derivative control algorithm, is based on the principle of controlling the error between the actual sampled data of the controlled object and the given reference data by superimposing the three algorithms of proportional, integral and derivative, so that the actual sampled data gradually approaches the reference data to achieve the control purpose.

[0049] Figure 1 A schematic diagram of an application scenario provided by an embodiment of the present invention. Figure 1 According to the measurement principle of electrochemical impedance spectroscopy, the electrochemical impedance of the electrochemical system is determined based on an AC excitation signal applied to the electrochemical system to be measured and a response signal caused by the excitation signal. Therefore, it is necessary to connect a measurement auxiliary circuit 20 outside the electrochemical system to be measured 10 to form a measurement loop 100, so that after a measurement device 30 for measuring electrochemical impedance spectroscopy introduces an excitation signal into the measurement loop 100, a corresponding response signal can be generated in the measurement loop 100.

[0050] Figure 2 A flow chart of an electrochemical impedance spectroscopy measurement method provided in an embodiment of the present invention. The method can be applied to Figure 1 The measuring device 30 shown. Figure 2 , the method comprises the following steps:

[0051] Step 101, obtaining an actual sampling signal of a measurement circuit where an electrochemical system is located.

[0052] Optionally, the actual sampling signal includes any one of a current signal and a voltage signal of the measurement loop.

[0053] Step 102: Obtain a reference sinusoidal signal, and modulate the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm to obtain an excitation signal.

[0054] In a possible implementation manner, the obtaining of the reference sinusoidal signal may be performed by reading a pre-stored reference sinusoidal signal I from a related storage device. ref (t) The sampling signal I ref(n), i.e., time-discontinuous signals, including the reference sinusoidal signal I ref (t) The sampling values ​​of multiple sampling points in at least one cycle {I ref (0),I ref (1), I ref (2), …}.

[0055] In a possible implementation manner, the sample data of the reference sinusoidal signal may be acquired in real time by means of function calculation using a related processing chip.

[0056] Step 103: input the excitation signal into the measurement loop.

[0057] Figure 3 The schematic diagram of generating an excitation signal provided by an embodiment of the present invention. Figure 3 Taking the current excitation method as an example, in the embodiment of the present invention, the sampling signal I(n) of the current signal of the measurement loop is compared with the reference sinusoidal signal I ref The control signal output by the PID control algorithm is used as an excitation signal and introduced into the measurement loop, so that its current signal gradually matches the reference sinusoidal signal, which is equivalent to applying a sinusoidal current signal to the electrochemical system to be measured.

[0058] Among them, ΔI(n)=I(n)-I ref (n), the process of obtaining the excitation signal by PID control of ΔI(n) can be expressed as the following formula:

[0059]

[0060] In the above formula, α(n) is the temporal discontinuity representation of the excitation signal α(s) under Laplace transform, k p ×ΔI(n) is the proportional control part, k p is the scale parameter; is the integral control part, k i is the integration parameter; k d ×(ΔI(n)-ΔI(n-1)) is the differential control part, k d is the differential parameter.

[0061] Step 104: Acquire a response signal of the measurement loop.

[0062] Step 105: Calculate the electrochemical impedance of the electrochemical system according to the response signal.

[0063] based on Figure 3As shown in the schematic diagram, after the current excitation signal is introduced into the measurement loop, the corresponding response signal is the voltage signal of the measurement loop, so step 104 can specifically be to obtain the voltage response signal of the measurement loop, that is, the voltage across the electrochemical system, and then the electrochemical impedance of the electrochemical system can be calculated according to the voltage response signal in step 105. On this basis, by adjusting the frequency of the excitation signal and obtaining the response signal corresponding to the excitation signal of different frequencies, the electrochemical impedance of the electrochemical system at different frequencies can be calculated, thereby obtaining the electrochemical impedance spectrum.

[0064] Optionally, in step 105, based on Ohm's law Calculate the electrochemical impedance Z, where represents the AC voltage across the electrochemical system, Indicates the AC current in the measurement circuit.

[0065] It should be noted that Figure 3 The schematic diagram shown takes the current excitation method as an example, that is, the current signal of the measurement loop is collected, and the current excitation signal is generated and introduced into the measurement loop, and the corresponding response signal is the voltage signal of the measurement loop; in other possible implementations of the present invention, a voltage excitation method can also be adopted, that is, the voltage signal of the measurement loop is collected, and the voltage excitation signal is generated according to the PID control algorithm and introduced into the measurement loop, and the corresponding response signal is the current signal of the measurement loop.

[0066] Optionally, when applied to electrochemical impedance spectroscopy measurement of a battery, if the battery capacity is large, a current excitation method may be used, and if the battery capacity is small, a voltage excitation method may be used.

[0067] As can be seen from the above description, the embodiment of the present invention introduces the output control signal as an excitation signal into the above-mentioned measurement loop through PID control of the difference between the actual sampling signal and the reference sinusoidal signal of the measurement loop where the electrochemical system is located, so that the actual sampling signal of the measurement loop gradually matches the reference sinusoidal signal, which is equivalent to applying a sinusoidal AC excitation signal to the electrochemical system to be measured, and the corresponding response signal is also an AC signal. The electrochemical impedance of the electrochemical system can be calculated based on the AC response signal. Then, the electrochemical impedance spectrum of the electrochemical system can be obtained according to the response signal corresponding to the excitation signal of different frequencies. Based on the embodiment of the present invention, the electrochemical impedance spectrum measurement does not require an AC signal generator, thereby reducing the measurement cost and the size of the measurement equipment, and can be conveniently and quickly applied to the impedance spectrum measurement of any electrochemical system.

[0068] Figure 4 A schematic diagram of a measurement circuit for measuring electrochemical impedance spectroscopy provided by an embodiment of the present invention. Figure 4In a possible implementation, the measurement auxiliary circuit 20 that forms a measurement loop with the electrochemical system may include: a DC transformer circuit 21 and a load resistor 22 .

[0069] The two input ends of the DC transformer circuit 21 are connected to the positive electrode and the negative electrode of the electrochemical system respectively, and the two output ends of the DC transformer circuit 21 are connected to the two ends of the load resistor 22 respectively. The DC transformer circuit 21 and the load resistor 22 are equivalent to Figure 1 The measurement auxiliary circuit 20 shown forms a measurement loop with the electrochemical system 10 .

[0070] The DC transformer circuit 21 is used to convert the high-power DC voltage output by the electrochemical system into a low-power DC voltage, or to convert the low-power DC voltage output by the electrochemical system into a high-power DC voltage, and then apply it to the load resistor 22. Figure 4 As shown, the load resistor 22 is also represented by R, the DC transformer circuit 21 is provided with a switch device S, a capacitor C, an inductor L and a diode D, and the input voltage V of the DC transformer circuit 21 is in , that is, the output voltage of the electrochemical system. By controlling the on and off of the switch device S, the charge and discharge state of the capacitor component C can be controlled: when the switch device S is on, the capacitor C is in a charging state, and when the switch device S is off, the capacitor C is in a discharging state; thereby changing the voltage across the capacitor component C, that is, the output voltage V of the DC transformer circuit 21. out , realized by high voltage V in Convert to low voltage V out .

[0071] Based on the above measurement loop, the actual sampling signal obtained in the above step 101 can be specifically the input current I of the DC transformer circuit 21. in In step 103, the excitation signal is input into the measurement circuit, which may be specifically: the excitation signal is input into the control signal terminal of the switch device S, so as to control the switch device S to be alternately turned on and off by the excitation signal, so that the capacitor C alternates between the charging state and the discharging state, thereby causing the measurement circuit to generate an AC response signal. By measuring the AC response signal, the electrochemical impedance of the electrochemical system can be calculated based on it.

[0072] Combination Figure 3 The PID control principle shown in the figure is that the measurement loop is the execution structure of the PID control system. Its input is the PID control signal, that is, the excitation signal α(s), which excites the measurement loop to generate an AC signal. The generated AC current signal I in Sampling is performed to obtain the actual current sampling signal I(n), which is fed back to the PID control process; the average state transfer function C(s) of the measurement loop can be expressed as:

[0073]

[0074] Where I(s) is the current signal I in In the Laplace transformation, s is the Laplace transformation parameter, R is the load resistance, C and L are the capacitance and inductance in the DC transformer circuit, respectively, V in is the input voltage of the DC transformer circuit.

[0075] Figure 4 In the DC transformer circuit, a P-channel enhanced metal oxide field effect transistor is used as the switch device S. In other implementations, other forms of circuit elements or switch circuits can also be sampled as the switch device S, which will not be repeated here.

[0076] It should be noted that Figure 4 The measurement auxiliary circuit and DC transformer circuit shown are only a specific implementation of the present invention, which can convert the high voltage output by the electrochemical system into a low voltage; in actual application scenarios, other forms of DC transformer circuits or other forms of measurement auxiliary circuits can also be sampled for voltage conversion to achieve the conversion of the low voltage output by the electrochemical system into a high voltage, so that the converted voltage range is easier to be measured by the measuring device or measuring equipment. According to the principle of the embodiment of the present invention, the same or similar technical effects as the embodiment of the present invention can be achieved through different measurement auxiliary currents or different quality transformer circuits, so they are all within the protection scope of the present invention.

[0077] In the above embodiment of the present invention, a DC transformer circuit and a load resistor are used to form a measurement loop with the electrochemical system to be measured, and an excitation signal is generated by collecting the input current signal of the DC transformer circuit using a PID control algorithm, and the excitation signal is introduced into the switch device of the DC transformer circuit to control the switch state change of the switch device, so that the measurement loop generates an AC response signal. The measurement auxiliary circuit formed by the above DC transformer circuit and the load resistor can be directly connected to the two electrode ports of the electrochemical system, which is equivalent to being connected in parallel with the working circuit of the electrochemical system, and will not affect the operating condition of its working circuit, and there is no need to disconnect the electrochemical system from its working circuit. Therefore, the embodiment of the present invention can realize the measurement of its electrochemical impedance spectrum under the normal operating conditions of the electrochemical system, that is, during the production and use of the electrochemical system, its electrochemical impedance spectrum can be measured at any time based on the embodiment of the present invention. In addition, since the DC transformer circuit in the measurement auxiliary circuit can convert the high voltage output by the electrochemical system into a low voltage that is more convenient for measurement, or convert the low voltage output by the electrochemical system into a high voltage that is more convenient for measurement, the embodiment of the present invention can be widely used in the measurement of electrochemical impedance spectra of low-power and high-power electrochemical systems.

[0078] In some application scenarios, the above embodiments of the present invention can be used to measure the electrochemical impedance spectrum of any battery system, such as a battery pack with a higher output voltage, a battery module, and a single battery with a lower output voltage. At the same time, during the electrochemical impedance spectrum measurement process, the battery system to be tested can operate under normal working conditions without being disconnected from the working circuit. Its electrochemical impedance spectrum can be measured anytime and anywhere, so that the internal state of the battery system can be grasped in time, the health status and life of the battery can be understood, and battery failures can be discovered in time.

[0079] Because the state of charge (SOC), that is, the ratio of its remaining power to the full capacity of the battery, of the battery component is constantly changing under normal operating conditions such as charging or discharging, the change in the state of charge △SOC is the difference in the state of charge of the battery component at two adjacent moments. To ensure the accuracy of the measurement effect and the measurement results, the smaller the △SOC of the battery component during the measurement process, the better. In actual application scenarios, the change in the state of charge of the battery component can be minimized by controlling the measurement cycle, the size of the road end current, etc. Optionally, electrochemical impedance spectroscopy measurements can be performed under conditions where the change in the state of charge of the battery component △SOC ≤ 5%.

[0080] In this embodiment, the measurement condition is set within ΔSOC≤5%, which can reduce the change of electrochemical impedance caused by rapid charging and discharging of the battery component during the measurement process and ensure the measurement accuracy.

[0081] In a possible implementation, in step 103, inputting the excitation signal into the measurement circuit may specifically include: performing pulse width modulation (PWM) on the excitation signal, and inputting the obtained pulse width modulation signal into the measurement circuit. Figure 4 The control signal terminal of the switching device S shown.

[0082] In the embodiment of the present invention, the excitation signal is adjusted to a pulse width modulation signal consisting of a simple high level and a low level through pulse width modulation, and the duty cycle of the pulse width modulation signal can be further adjusted as needed, which is more conducive to controlling the switch device S.

[0083] Optionally, by pulse width modulating the excitation signal, the duty cycle of the pulse width modulated signal can be limited to any range within (0, 1) according to actual control requirements, thereby controlling the ratio of the on-time and off-time of the switching device, that is, controlling the ratio of the charging time and discharging time of the capacitor in the DC transformer circuit, and ultimately achieving the purpose of controlling the current and voltage of the measurement circuit.

[0084] In a possible implementation, the actual sampling signal of the measurement circuit where the electrochemical system is located in step 101 may specifically include: 1 The measurement loop is sampled to obtain the actual sampling signal.

[0085] The above preset sampling interval t 1 , that is, the sampling interval for sampling the measurement loop. Its minimum value is related to the performance of the relevant hardware equipment. The better the performance of the hardware equipment, the shorter the sampling interval. 1 The smaller the value can be. Set the preset sampling interval t before the measurement starts. 1 , the minimum value allowed by the hardware device can be directly used. In the entire measurement process, the preset sampling interval t 1 Take samples.

[0086] Accordingly, obtaining the reference sinusoidal signal in the above step 102 includes:

[0087] Step 1021: For the actual sampling signal obtained at each sampling moment, obtain a sample data of the reference sinusoidal signal.

[0088] As mentioned above, the reference sinusoidal signal can be represented by the sampling values ​​{I ref (0),I ref (1), I ref (2), ...} in the form of pre-stored in the relevant storage unit.

[0089] Each time an actual sampling signal is obtained, a sample data is obtained as a reference value, and then the difference between the two is modulated through the PID control algorithm, that is, the time interval between two adjacent readings of the sample data of the reference sine signal is also t 1 , if the number of sample data in one period of the reference sinusoidal signal is N, then the period of the reference sinusoidal signal used at this time is t 2 =N*t 1 . Reference Fig.11 , the reference sine signal has 12 sampling points in one cycle (sampling points 1 and 13 are repeated sampling points), corresponding to 12 sample data, so in t 1 When the actual sampling signal and the corresponding sample data are obtained at intervals, the period t of the corresponding reference sinusoidal signal 2 =12*t 1 .

[0090] In a possible implementation, after the i-th actual sampling signal I(i) is obtained by sampling at the i-th sampling time, a sampling data of the reference sinusoidal signal can be read from the relevant storage unit, such as I ref(0), and then according to the PID control algorithm, the difference between the two is ΔI(i)=I(i)-I ref (0) modulation; after sampling the i+1th actual sampling signal I(i+1) at the next sampling time, i.e., the i+1th sampling time, the next sampling data of the reference sinusoidal signal is read from the relevant storage unit, i.e., I ref (1), and then according to the PID control algorithm, the difference between the two is ΔI(i+1)=I(i+1)-I ref (1) Modulation... and so on. At this time, since the sample data of the actual sampling signal, the reference sine signal and the difference between the two are one-to-one corresponding, the period of the excitation signal obtained by PID control is consistent with the preset sampling interval t 1 , the number of sample data N in one cycle of the reference sine signal is also consistent with the period of the reference sine signal at this time, that is, N*t 1 ; Correspondingly, the frequency of the excitation signal is 1 / (N*t 1 ).

[0091] In other possible implementations, the period of the excitation signal, that is, the frequency of the excitation signal, can be adjusted by cyclically reading the same sample data of the reference sinusoidal signal for a plurality of consecutive actual sampling signals to obtain an excitation signal of a desired frequency.

[0092] The above step 1021 obtains a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment, which may specifically include:

[0093] Determine the number of cycles m according to the preset frequency f;

[0094] For the m consecutive actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained;

[0095] For the m consecutive actual sampling signals obtained from the i+mth to the i+2m-1th sampling moments, obtaining the j+1th sample data of the reference sinusoidal signal;

[0096] Wherein, i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t 1 .

[0097] The frequency of the excitation signal required in the actual application scenario, that is, the preset frequency f, is known and can be calculated according to the above relationship 1 / f=m*N*t 1 Determine m. Assuming m = 3, after obtaining the actual sampling signal I(i) at the i-th sampling moment, read the j-th sample data I ref(0), as the sample data corresponding to I(i); after obtaining the actual sampling signal I(i+1) at the i+1th sampling moment, the jth sample data I is still read ref (0) as the sample data corresponding to I(i+1); after the actual sampling signal I(i+2) is obtained at the i+2th (i.e., i+m-1=i+3-1=i+2)th sampling moment, the jth sample data I is still read. ref (0), as the sample data corresponding to I(i+2); after obtaining the actual sampling signal I(i+3) at the i+3th (i.e., i+m)th sampling time, read the j+1th sample data, i.e., I ref (1), as the sample data corresponding to I(i+3); after obtaining the actual sampling signal I(i+4) at the i+4th sampling moment, the j+1th sample data is still read, that is, I ref (1) is used as the sample data corresponding to I(i+4); after the actual sampling signal I(i+5) is obtained at the i+5th (i.e., i+2m-1=i+2*3-1=i+5)th sampling time, the j+1th sample data is still read, i.e., I ref (1), as the sample data corresponding to I(i+5) ... and so on, that is, every m consecutive actual sampling signals correspond to one sample data.

[0098] Accordingly, in the above step 102, the difference between the actual sampling signal and the reference sinusoidal signal is modulated according to the PID control algorithm to obtain the excitation signal, which may include:

[0099] The difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal is modulated according to the PID control algorithm to obtain an excitation signal with a frequency equal to the preset frequency f.

[0100] Since each of m consecutive actual sampling signals corresponds to one sample data, the period of the obtained excitation signal is m*N*t 1 , that is, the frequency of the excitation signal is 1 / (m*N*t 1 )=f. It can be seen that the purpose of adjusting the frequency of the excitation signal can be achieved through the above method, and an excitation signal with a frequency of the preset frequency f can be obtained.

[0101] Optionally, in the embodiment of the present invention, due to the preset sampling interval t 1 The minimum value of is limited by the hardware performance, so the maximum value of the excitation signal frequency is limited, that is, the frequency when m=1 is 1 / (N*t 1 ). In actual application scenarios, the frequency of the excitation signal can be controlled to be up to 3kHz, and the minimum frequency is unlimited. The larger the m, the smaller the frequency of the excitation signal.

[0102] Based on the above embodiments, by controlling the frequency of the output excitation signal during the PID control process, the frequency of the current and voltage in the measurement loop can be controlled, so that the electrochemical impedance at different frequencies can be obtained, that is, the electrochemical impedance spectrum can be obtained.

[0103] Based on the same inventive concept, an embodiment of the present invention further provides a method for generating an excitation signal, which can be applied to scenarios requiring an AC excitation signal, such as electrochemical impedance spectroscopy measurement. Figure 5 For a flow chart of the excitation signal generation method, refer to Figure 5 , the method comprises the following steps:

[0104] Step 201, obtaining the actual sampling signal of the target loop.

[0105] Step 202, obtaining a reference sinusoidal signal, and modulating the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm to obtain an excitation signal;

[0106] Step 203: input the excitation signal into the target loop.

[0107] The target circuit can be any circuit that requires an AC excitation signal, including but not limited to the measurement circuit of the electrochemical system in the electrochemical impedance spectroscopy measurement method described above. The actual sampling signal includes any one of the current signal and the voltage signal of the target circuit.

[0108] In a possible implementation, obtaining the actual sampling signal of the target loop in step 201 may include: 1 The target loop is sampled to obtain the actual sampling signal.

[0109] Accordingly, obtaining the reference sinusoidal signal in step 202 may specifically include:

[0110] Step 2021, for the actual sampling signal obtained at each sampling moment, obtain a sample data of the reference sinusoidal signal.

[0111] In a possible implementation, the above step 2021 may specifically include:

[0112] Determine the number of cycles m according to the preset frequency f;

[0113] For the m consecutive actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained;

[0114] For the m consecutive actual sampling signals obtained from the i+mth to the i+2m-1th sampling moments, obtaining the j+1th sample data of the reference sinusoidal signal;

[0115] Wherein, i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t 1 Correspondingly, step 202 modulates the difference between the actual sampling signal and the reference sinusoidal signal according to the PID control algorithm to obtain an excitation signal, which may specifically include:

[0116] The difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal is modulated according to the PID control algorithm to obtain an excitation signal with a frequency equal to the preset frequency f.

[0117] The above steps 201 to 203 and steps 101 to 103 in the previous embodiment are based on the same principle and can be referenced to each other, and the similarities will not be repeated here.

[0118] The excitation signal generation method provided by the embodiment of the present invention can be applied to a variety of scenarios requiring AC excitation signals, including electrochemical impedance measurement. Based on actual signals such as current or voltage of the target circuit requiring the AC excitation signal, the AC excitation signal is obtained according to the PID control algorithm, and the AC excitation signal is finally introduced into the target circuit. No independent AC signal generator or other equipment is required. The AC excitation signal can be obtained by a chip or processor embedded with the PID control algorithm, thereby reducing the use cost and the size of related equipment. At the same time, the embodiment of the present invention can also change the frequency of the AC excitation signal through PID control to meet different application requirements.

[0119] Based on the same concept, the present invention also provides an electrochemical impedance spectroscopy measuring device, which can be applied to Figure 1 The measuring device 30 shown. Figure 6 The structure block diagram of the electrochemical impedance spectroscopy measuring device 300 of the embodiment of the present invention is shown, and the device 300 includes:

[0120] A first acquisition module 301 is used to acquire an actual sampling signal of a measurement circuit where an electrochemical system is located; the actual sampling signal includes any one of a current signal and a voltage signal;

[0121] The algorithm control module 302 is used to obtain a reference sinusoidal signal, and modulate the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm to obtain an excitation signal;

[0122] A signal output module 303, used for inputting the excitation signal into the measurement loop;

[0123] A second acquisition module 304, used to acquire a response signal of the measurement loop;

[0124] The impedance analysis module 305 is used to calculate the electrochemical impedance of the electrochemical system according to the response signal.

[0125] In one possible implementation, the measurement circuit includes the electrochemical system, the DC transformer circuit and the load resistor; accordingly, the signal output module 303 is used to input the excitation signal into the measurement circuit, which may specifically include: the signal output module 303 is used to input the excitation signal into the switching device of the DC transformer circuit to control the switching state of the switching device.

[0126] In a possible implementation, the signal output module 303 is used to input the excitation signal into the measurement circuit, which may specifically include: the signal output module 303 is used to perform pulse width modulation on the excitation signal, and input the obtained pulse width modulated signal into the measurement circuit.

[0127] In a possible implementation, the first acquisition module 301 is used to acquire the actual sampling signal of the measurement circuit where the electrochemical system is located, which may include: the first acquisition module 301 is used to obtain the actual sampling signal of the measurement circuit where the electrochemical system is located according to the preset sampling interval t 1 Sampling the measurement loop to obtain the actual sampling signal;

[0128] The algorithm control module 302 is used to obtain the reference sinusoidal signal, which may include: the algorithm control module 302 is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment.

[0129] In a possible implementation, the algorithm control module 302 is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment, which may include: the algorithm control module 302 is used to determine the number of cycles m according to the preset frequency f; for the consecutive m actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained; for the consecutive m actual sampling signals obtained from the i+m-th to the i+2m-1-th sampling moments, the j+1-th sample data of the reference sinusoidal signal is obtained; wherein i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t 1 .

[0130] Correspondingly, the algorithm control module 302 is used to modulate the difference between the actual sampling signal and the reference sinusoidal signal according to the PID control algorithm to obtain an excitation signal, which may specifically include: the algorithm control module 302 is used to modulate the difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal according to the PID control algorithm to obtain an excitation signal with a frequency of the preset frequency f.

[0131] The embodiment of the present invention controls the difference between the actual sampling signal and the reference sinusoidal signal of the measurement loop where the electrochemical system is located by PID control, and introduces the output control signal as an excitation signal into the above-mentioned measurement loop, so that the actual sampling signal of the measurement loop gradually matches the reference sinusoidal signal, which is equivalent to applying a sinusoidal AC excitation signal to the electrochemical system to be measured, and the corresponding response signal is also an AC signal. The electrochemical impedance of the electrochemical system can be calculated according to the AC response signal. Then, the electrochemical impedance spectrum of the electrochemical system can be obtained according to the response signal corresponding to the excitation signal of different frequencies. Based on the embodiment of the present invention, the electrochemical impedance spectrum measurement is performed without the need for an AC signal generator, thereby reducing the measurement cost and the size of the measuring equipment, and can be conveniently and quickly applied to the impedance spectrum measurement of the electrochemical system in a variety of scenarios. At the same time, since the above-mentioned measurement loop is connected in parallel with the working loop of the electrochemical system, it will not affect the operating condition of its working loop, and the electrochemical system does not need to be disconnected from its working loop. Therefore, the embodiment of the present invention can realize the measurement of its electrochemical impedance spectrum under the normal operating conditions of the electrochemical system, that is, during the production and use of the electrochemical system, its electrochemical impedance spectrum can be measured at any time based on the embodiment of the present invention. In addition, since the high voltage output by the electrochemical system can be converted into a low voltage that is easier to measure, or the low voltage output by the electrochemical system can be converted into a high voltage that is easier to measure, the embodiments of the present invention can be widely used in electrochemical impedance spectroscopy measurements of low-power and high-power electrochemical systems through different measurement auxiliary circuits or different DC transformer circuits.

[0132] Based on the same concept, the embodiment of the present invention also provides an excitation signal generating device, see Figure 7 The structure block diagram of the excitation signal generating device 400 shown in FIG. 4 includes:

[0133] A first acquisition module 401 is used to acquire an actual sampling signal of a target loop; the actual sampling signal includes any one of a current signal and a voltage signal of the target loop;

[0134] The algorithm control module 402 is used to obtain a reference sinusoidal signal, and modulate the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm to obtain an excitation signal;

[0135] The signal output module 403 is used to input the excitation signal into the target loop.

[0136] In a possible implementation, the first acquisition module 401 is used to acquire the actual sampling signal of the measurement circuit where the electrochemical system is located, which may include: the first acquisition module 401 is used to obtain the actual sampling signal of the measurement circuit where the electrochemical system is located according to the preset sampling interval t 1 Sampling the measurement loop to obtain the actual sampling signal;

[0137] Accordingly, the algorithm control module 402 is used to obtain the reference sinusoidal signal, which may include:

[0138] The algorithm control module 402 is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment.

[0139] In a possible implementation, the algorithm control module 402 is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment, which may include: the algorithm control module 402 is used to determine the number of cycles m according to the preset frequency f; for the consecutive m actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained; for the consecutive m actual sampling signals obtained from the i+m-th to the i+2m-1-th sampling moments, the j+1-th sample data of the reference sinusoidal signal is obtained; wherein i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t 1 .

[0140] Correspondingly, the algorithm control module 402 is used to modulate the difference between the actual sampling signal and the reference sinusoidal signal according to the PID control algorithm to obtain an excitation signal, which may specifically include: the algorithm control module 402 is used to modulate the difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal according to the PID control algorithm to obtain an excitation signal with a frequency of the preset frequency f.

[0141] It should be noted that, for the embodiments of the above-mentioned electrochemical impedance measurement device and excitation signal generating device, since they are basically similar to the embodiments of the electrochemical impedance measurement method and excitation signal generating method described above, only a brief description of the device embodiments is given, and relevant details can be found in the description of the method embodiment part.

[0142] Based on the same concept, an embodiment of the present invention further provides an electrochemical impedance spectroscopy measuring device. Figure 8 is a structural block diagram of the electrochemical impedance spectroscopy measurement device 500. Figure 8 , the device 500 may include: an auxiliary circuit unit 510 , a signal measuring unit 520 and a core processing unit 530 .

[0143] The auxiliary circuit unit 510 is provided with an input port for connecting to the electrochemical system to be measured, thereby forming a measurement loop with the electrochemical system.

[0144] The signal measurement unit 520 is connected to the auxiliary circuit unit 510 or the electrochemical system, and is used to collect the signal of the measurement circuit.

[0145] The core processing unit 530 is connected to the auxiliary circuit unit 510 and the signal measurement unit 520, respectively, and is used to obtain the actual sampling signal of the measurement loop where the electrochemical system is located through the signal measurement unit 520, and the actual sampling signal includes any one of a current signal and a voltage signal; obtain a reference sinusoidal signal, modulate the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm to obtain an excitation signal; input the excitation signal into the measurement loop formed by the auxiliary circuit unit 510; and then obtain a response signal of the measurement loop through the signal measurement unit 520, and calculate the electrochemical impedance of the electrochemical system according to the response signal.

[0146] In one possible implementation, the core processing unit 530 may be implemented by a chip, and its processing steps, i.e., the steps of the electrochemical impedance spectroscopy measurement method embodiment described above, are written into the chip in the form of computer executable instructions. When the chip executes the instructions, the functions of the core processing unit 530 may be implemented.

[0147] The electrochemical impedance spectrum measuring device provided by the embodiment of the present invention, the core processing unit generates an excitation signal according to the PID control algorithm and introduces it into the measurement loop, which is equivalent to applying an AC disturbance to the measurement loop, generating an AC response signal, and then the electrochemical impedance spectrum of the electrochemical system can be calculated according to the AC response signal, without the need to use an AC signal generator, so the equipment cost and equipment size can be reduced. At the same time, an auxiliary circuit unit is provided in the measuring device, which is used to connect with the electrochemical system to form a measurement loop. When using the device, the relevant personnel do not need to prepare the circuit components required for the measurement loop. They only need to connect the device to the electrochemical system to start the measurement, realizing plug-and-play, which is convenient and fast. Moreover, the measurement loop formed by the device is connected in parallel with the working loop of the electrochemical system itself, and the measurement of its electrochemical impedance spectrum can be completed under the normal working conditions of the electrochemical system, so as to obtain the internal state of the electrochemical system anytime and anywhere, timely discover possible faults, and ensure the normal operation of the relevant equipment or system in its application scenario.

[0148] In a possible implementation, the auxiliary circuit unit 510 may sample Figure 4 The measurement auxiliary circuit 20 shown may include a DC transformer circuit and a load resistor; wherein the input end of the DC transformer circuit serves as the input port of the auxiliary circuit unit 510, connected to the electrochemical system, and can convert the high DC voltage output by the electrochemical system into a low DC voltage.

[0149] It should be noted that the measuring device 500 provided in the embodiment of the present invention has an auxiliary circuit unit 510 built in, which is equivalent to Figure 1 The measurement auxiliary circuit 20 and the measurement device 30 shown are combined into one device, so that no other circuit components need to be prepared to form a measurement circuit during measurement. Of course, in other possible implementations, the auxiliary circuit unit 510 may not be used, but a measurement circuit may be formed by an external measurement auxiliary circuit and the electrochemical system to be measured, and the electrochemical impedance spectrum measurement of the electrochemical system may be achieved by the measurement device 500 provided in the embodiment of the present invention. The principle and effect are the same or similar to those in the embodiment of the present invention, and are also within the protection scope of the present invention.

[0150] It can be seen that the electrochemical impedance spectroscopy measurement device provided in the embodiment of the present invention can not only measure the impedance spectrum of a low-power electrochemical system, but also measure the impedance spectrum of a high-power electrochemical system, thereby expanding the application scenarios of the device.

[0151] In a possible implementation, the DC transformer circuit in the auxiliary circuit unit 510 includes a switch device, and the output voltage of the DC transformer circuit can be controlled by controlling the switch state of the switch device. Accordingly, the core processing unit 530 is used to input the excitation signal into the measurement loop, which may specifically include: the core processing unit 530 is used to input the excitation signal into the switch device of the DC transformer circuit to control the switch state of the switch device, thereby changing the voltage and current of the measurement loop.

[0152] The structure of the DC transformer circuit can be referred to Figure 4 As shown, the auxiliary circuit unit 510 is equivalent to a charge and discharge control circuit, which controls the charge and discharge process of the energy storage element, namely the capacitor C, by controlling the switching state of its switch device, thereby realizing the voltage transformation function and enabling the circuit to generate an AC response signal.

[0153] In a possible implementation, the core processing unit 530 is used to input the excitation signal into the measurement loop, which may specifically include: the core processing unit 530 is used to perform pulse width modulation on the excitation signal, and input the obtained pulse width modulated signal into the measurement loop.

[0154] Optionally, when the core processing unit 530 is implemented in a chip manner, the pulse width modulation signal may be output through a general purpose input / output (GPIO) port of the chip.

[0155] In a possible implementation, the core processing unit 530 is used to obtain the actual sampling signal of the measurement circuit where the electrochemical system is located through the signal measurement unit, which may include: the core processing unit 530 is used to, according to the preset sampling interval t 1 Acquiring the actual sampling signal;

[0156] Accordingly, the core processing unit 530 is used to obtain a reference sinusoidal signal, including:

[0157] The core processing unit 530 is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment.

[0158] In a possible implementation, the core processing unit 530 is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment, which may include: the core processing unit 530 is used to determine the number of cycles m according to the preset frequency f; for the consecutive m actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained; for the consecutive m actual sampling signals obtained from the i+m-th to the i+2m-1-th sampling moments, the j+1-th sample data of the reference sinusoidal signal is obtained; wherein i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t 1 .

[0159] Correspondingly, the core processing unit 530 is used to modulate the difference between the actual sampling signal and the reference sinusoidal signal according to the PID control algorithm to obtain an excitation signal, which may specifically include: the core processing unit 530 is used to modulate the difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal according to the PID control algorithm to obtain an excitation signal with a frequency of the preset frequency f.

[0160] It can be seen that the core processing unit 530 can obtain excitation signals of different frequencies. By introducing excitation signals of different frequencies into the measurement circuit of the electrochemical system, the measurement circuit can generate response signals of different frequencies, and then the electrochemical impedance at different frequencies can be obtained to form an electrochemical impedance spectrum.

[0161] Optionally, the core processing unit 530 can be implemented by a chip, which can integrate an analog-to-digital conversion unit, a core computing unit, a high-frequency clock unit, etc., wherein the analog-to-digital conversion unit converts the analog electrical signal of the measurement loop collected by the signal measurement unit 520 into a digital signal, which is then used by the core computing unit to execute a PID control algorithm and generate an excitation signal. Finally, the excitation signal is pulse-width modulated by a high-frequency clock unit, and the obtained pulse-width modulated signal is output to the auxiliary circuit unit 510 to control the periodic opening and closing of the switching device of the DC transformer circuit therein.

[0162] In a possible implementation, a storage module may be provided in the core processing unit 530 to store at least one of the following data: sample data of the reference sinusoidal signal and electrochemical impedance measurement results. Optionally, the storage module may be a random access memory (RAM).

[0163] In other possible implementations, a storage unit may be provided in the electrochemical impedance spectroscopy measurement device; the storage unit, as a unit existing in parallel with the core processing unit 530, may also store at least one of the sample data of the reference sinusoidal signal, the electrochemical impedance measurement result and other data; at the same time, storage units with different storage capacities may be configured according to the usage scenario to store more sample data and measurement data, which is conducive to the comprehensive analysis of various indicators or parameters such as the health of the electrochemical system. Optionally, the storage unit may be a Mini SD Card (English full name: Secure Digital Memory Card) integrated in the above device.

[0164] In a possible embodiment, the electrochemical impedance spectroscopy measuring device further includes a communication unit. The communication unit is connected to the communication serial port in the core processing unit 530, and is used to transmit the electrochemical impedance measurement results obtained by the core processing unit 530 and the excitation signal, response signal and other data of the measurement circuit to an external device, such as a computer, a mobile phone and other devices, through wired communication or wireless communication, so that the above data can be stored and displayed by the external device, and the measurement results can be conveniently and intuitively displayed to relevant personnel. At the same time, the PID control parameters, i.e., the proportional parameters, integral parameters, differential parameters, and the required excitation signal frequency and other parameters mentioned above, can be input to the core processing unit 530 through the communication unit to achieve accurate control of the electrochemical impedance spectroscopy measurement process and improve measurement accuracy.

[0165] Fig. 9 This is a structural diagram of an electrochemical impedance spectroscopy measurement device 500 implemented based on an integrated circuit board according to an embodiment of the present invention. Fig. 9In a possible implementation, the auxiliary circuit unit 510, the signal measurement unit 520 and the core processing unit 530 can be integrated on a circuit board 560. Meanwhile, the communication unit 540 can also be integrated on the circuit board 560. The circuit board 560 is provided with a plurality of external ports, including but not limited to:

[0166] The electrochemical system connection port 551 is connected to the input port of the auxiliary circuit unit 510;

[0167] A measurement port 552 connected to an input port of a signal measurement unit;

[0168] The power port 553 is connected to an external power source to supply power to other units on the circuit board 560 .

[0169] It can be seen from the above embodiments that the electrochemical impedance spectroscopy measurement device provided in the embodiments of the present invention has low cost, small size, and is easy to use. It can be applied to electrochemical impedance spectroscopy measurement of various electrochemical systems in various scenarios anytime and anywhere. The measurement device can also be remotely connected through a smart device to view the measurement results in time and understand information such as the health status of the electrochemical system.

[0170] Fig.10 FIG. 1 is a structural block diagram of an electronic device provided by an embodiment of the present invention. Fig.10 As shown, the electronic device 600 may include a processor 601 and a memory 602; the memory 602 may be coupled to the processor 601. It is worth noting that the Fig.10 It is exemplary; other types of structures may also be used to supplement or replace this structure to achieve the same or similar functions.

[0171] In one possible embodiment, the functions of the electrochemical impedance spectroscopy measuring device 300 can be integrated into the processor 601. The processor 601 can be configured to perform all or part of the steps in the above electrochemical impedance spectroscopy measuring method embodiment. In another possible embodiment, the electrochemical impedance spectroscopy measuring device 300 can be configured separately from the processor 601, for example, the electrochemical impedance spectroscopy measuring device 300 can be configured as a chip connected to the processor 601, and the electrochemical impedance spectroscopy measurement is achieved through the control of the processor 601.

[0172] In one possible implementation, the functions of the excitation signal generating device 400 may be integrated into the processor 601. The processor 601 may be configured to perform operations of all or part of the steps in the above-mentioned excitation signal generating method embodiment. In another possible implementation, the excitation signal generating device 400 may be configured separately from the processor 601, for example, the excitation signal generating device 400 may be configured as a chip connected to the processor 601, and the excitation signal is generated under the control of the processor 601.

[0173] In addition, in some optional implementations, the electronic device 600 may also include: a communication module, an input unit, an audio processor, a display, a power supply, etc. It is worth noting that the electronic device 600 does not necessarily include Fig.10 In addition, the electronic device 600 may also include Fig.10 For components not shown, reference may be made to the prior art.

[0174] An embodiment of the present invention also provides a computer-readable storage medium capable of implementing all the steps in the electrochemical impedance spectroscopy measurement method and the excitation signal generation method in the above-mentioned embodiments. A computer program is stored on the computer-readable storage medium. When the computer program is executed by a processor, all the steps in the electrochemical impedance spectroscopy measurement method or the excitation signal generation method in the above-mentioned embodiments are implemented.

[0175] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device and system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0176] Although one or more embodiments of this specification provide method operation steps as described in the embodiments or flowcharts, more or fewer operation steps may be included based on conventional or non-creative labor. The order of steps listed in the embodiments is only one way of executing the order of many steps and does not represent the only execution order. When the actual device or client product is executed, it can be executed in the order of the method shown in the embodiments or the drawings or in parallel (for example, in a parallel processor or multi-threaded processing environment).

[0177] It should be understood by those skilled in the art that the embodiments of this specification may be provided as methods, devices (systems) or computer program products. Therefore, the embodiments of this specification may take the form of complete hardware embodiments, complete software embodiments or embodiments combining software and hardware. Moreover, one or more embodiments of this specification may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0178] In the description of the present application, it should be noted that the terms "upper", "lower", "inside", "outside", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships in the working state of the present application. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present application.

[0179] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect" and "connect" should be understood in a broad sense. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0180] The present application has been described above in conjunction with preferred embodiments, but these embodiments are only exemplary and serve only as an illustration. On this basis, various replacements and improvements may be made to the present application, all of which fall within the scope of protection of the present application.

Claims

1. A method for measuring electrochemical impedance spectroscopy, characterized in that: include: Acquire an actual sampling signal of a measurement circuit where the electrochemical system is located; the actual sampling signal includes any one of a current signal and a voltage signal; Acquire a reference sinusoidal signal, and modulate the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm to obtain an excitation signal; inputting the excitation signal into the measurement circuit; Acquiring a response signal of the measurement loop; Calculating the electrochemical impedance of the electrochemical system according to the response signal; The electrochemical impedance spectroscopy measurement method is applied to an electrochemical impedance spectroscopy measurement device; The electrochemical impedance spectroscopy measuring device comprises a measurement auxiliary circuit; the measurement auxiliary circuit comprises a DC transformer circuit and a load resistor; The measurement auxiliary circuit is connected to the electrochemical system to form the measurement loop; The obtaining of the actual sampling signal of the measurement circuit where the electrochemical system is located includes: sampling the measurement circuit according to a preset sampling interval t1 to obtain the actual sampling signal; The obtaining of the reference sinusoidal signal comprises: obtaining a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment; The step of obtaining a sample data of the reference sinusoidal signal from the actual sampling signal obtained at each sampling moment includes: Determine the number of cycles m according to the preset frequency f; For the m consecutive actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained; For the m consecutive actual sampling signals obtained from the i+mth to the i+2m-1th sampling moments, obtaining the j+1th sample data of the reference sinusoidal signal; Wherein, i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t1; The step of modulating the difference between the actual sampling signal and the reference sinusoidal signal according to the PID control algorithm to obtain an excitation signal includes: The difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal is modulated according to the PID control algorithm to obtain an excitation signal with a frequency equal to the preset frequency f.

2. The method according to claim 1, characterized in that The step of inputting the excitation signal into the measurement circuit comprises: The excitation signal is input into the switch device of the DC transformer circuit to control the switch state of the switch device.

3. The method according to claim 1, characterized in that Inputting the excitation signal into the measurement loop comprises: The excitation signal is pulse-width modulated, and the obtained pulse-width modulated signal is input into the measurement loop.

4. A method for generating an excitation signal, characterized in that: The method comprises: Acquire an actual sampling signal of a target circuit; the actual sampling signal includes any one of a current signal and a voltage signal of the target circuit; Acquire a reference sinusoidal signal, modulate the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm to obtain an excitation signal, and input the excitation signal into the target loop; The obtaining of the actual sampling signal of the target loop includes: sampling the target loop according to a preset sampling interval t1 to obtain the actual sampling signal; The obtaining of a reference sinusoidal signal comprises: For the actual sampling signal obtained at each sampling moment, obtaining a sample data of the reference sinusoidal signal; The step of obtaining a sample data of the reference sinusoidal signal from the actual sampling signal obtained at each sampling moment includes: Determine the number of cycles m according to the preset frequency f; For the m consecutive actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained; For the m consecutive actual sampling signals obtained from the i+mth to the i+2m-1th sampling moments, obtaining the j+1th sample data of the reference sinusoidal signal; Wherein, i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t1; The step of modulating the difference between the actual sampling signal and the reference sinusoidal signal according to the PID control algorithm to obtain an excitation signal includes: The difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal is modulated according to the PID control algorithm to obtain an excitation signal with a frequency equal to the preset frequency f.

5. An electrochemical impedance spectroscopy measuring device, characterized in that: include: A first acquisition module is used to acquire an actual sampling signal of a measurement circuit where the electrochemical system is located; the actual sampling signal includes any one of a current signal and a voltage signal; An algorithm control module, used for obtaining a reference sinusoidal signal, modulating the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm, and obtaining an excitation signal; A signal output module, used for inputting the excitation signal into the measurement circuit; A second acquisition module, used to acquire a response signal of the measurement loop; an impedance analysis module, used for calculating the electrochemical impedance of the electrochemical system according to the response signal; The electrochemical impedance spectroscopy measuring device is applied to electrochemical impedance spectroscopy measuring equipment; The electrochemical impedance spectroscopy measuring device comprises a measurement auxiliary circuit; the measurement auxiliary circuit comprises a DC transformer circuit and a load resistor; The measurement auxiliary circuit is connected to the electrochemical system to form the measurement loop; The first acquisition module is used to acquire the actual sampling signal of the measurement circuit where the electrochemical system is located, including: the first acquisition module is used to sample the measurement circuit according to a preset sampling interval t1 to obtain the actual sampling signal; The algorithm control module is used to obtain a reference sinusoidal signal, including: the algorithm control module is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment; The algorithm control module is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment, including: The algorithm control module is used to determine the number of cycles m according to the preset frequency f; for the continuous m actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained; for the continuous m actual sampling signals obtained from the i+m-th to the i+2m-1-th sampling moments, the j+1-th sample data of the reference sinusoidal signal is obtained; wherein i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t1; The algorithm control module is used to modulate the difference between the actual sampling signal and the reference sinusoidal signal according to the PID control algorithm to obtain an excitation signal, including: The algorithm control module is used to modulate the difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal according to the PID control algorithm to obtain an excitation signal with a frequency of the preset frequency f.

6. The device according to claim 5, characterized in that The signal output module is used to input the excitation signal into the measurement loop, and includes: The signal output module is used to input the excitation signal into the switch device of the DC transformer circuit to control the switch state of the switch device.

7. The device according to claim 5, characterized in that The signal output module is used to input the excitation signal into the measurement loop, and includes: The signal output module is used to perform pulse width modulation on the excitation signal and input the obtained pulse width modulation signal into the measurement loop.

8. An electrochemical impedance spectroscopy measuring device, characterized in that: include: An auxiliary circuit unit is connected to the electrochemical system to be measured and forms a measurement loop with the electrochemical system; A signal measuring unit, used for collecting the signal of the measuring loop; A core processing unit connected to the auxiliary circuit unit and the signal measurement unit, and used for obtaining an actual sampling signal of a measurement circuit where an electrochemical system is located through the signal measurement unit, wherein the actual sampling signal includes any one of a current signal and a voltage signal; obtaining a reference sinusoidal signal, modulating the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm to obtain an excitation signal; inputting the excitation signal into the measurement circuit; obtaining a response signal of the measurement circuit through the signal measurement unit, and calculating the electrochemical impedance of the electrochemical system according to the response signal; The auxiliary circuit unit includes: a DC transformer circuit and a load resistor; The core processing unit is used to obtain the actual sampling signal of the measurement circuit where the electrochemical system is located through the signal measurement unit, including: the core processing unit is used to obtain the actual sampling signal according to the preset sampling interval t1; The core processing unit is used to obtain a reference sinusoidal signal, including: the core processing unit is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment; The core processing unit is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment, including: The core processing unit is used to determine the number of cycles m according to the preset frequency f; for the continuous m actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained; for the continuous m actual sampling signals obtained from the i+m-th to the i+2m-1-th sampling moments, the j+1-th sample data of the reference sinusoidal signal is obtained; wherein i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t1; The core processing unit is used to modulate the difference between the actual sampling signal and the reference sinusoidal signal according to the PID control algorithm to obtain an excitation signal, including: The core processing unit is used to modulate the difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal according to the PID control algorithm to obtain an excitation signal with a frequency of the preset frequency f.

9. The device according to claim 8, characterized in that The DC transformer circuit includes a switch device; The core processing unit is used to input the excitation signal into the measurement loop, including: the core processing unit is used to input the excitation signal into the switch device of the DC transformer circuit to control the switch state of the switch device.

10. The device according to claim 8, characterized in that The core processing unit is used to input the excitation signal into the measurement loop, including: The core processing unit is used for performing pulse width modulation on the excitation signal and inputting the obtained pulse width modulation signal into the measurement loop.

11. The device according to claim 8, characterized in that The core processing unit comprises: The storage module is used to store at least one of the following data: sample data of the reference sinusoidal signal and electrochemical impedance measurement results.

12. The device according to claim 8, characterized in that The device also includes: The communication unit is connected to the core processing unit and is used to transmit the electrochemical impedance measurement result obtained by the core processing unit to an external device.

13. An excitation signal generating device, characterized in that: include: A first acquisition module, configured to acquire an actual sampling signal of a target loop; the actual sampling signal includes any one of a current signal and a voltage signal of the target loop; An algorithm control module, used for obtaining a reference sinusoidal signal, modulating the difference between the actual sampling signal and the reference sinusoidal signal according to a PID control algorithm, and obtaining an excitation signal; A signal output module, used for inputting the excitation signal into the target circuit; The first acquisition module is used to acquire the actual sampling signal of the measurement circuit where the electrochemical system is located, including: the first acquisition module is used to sample the measurement circuit according to a preset sampling interval t1 to obtain the actual sampling signal; The algorithm control module is used to obtain a reference sinusoidal signal, including: The algorithm control module is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment; The algorithm control module is used to obtain a sample data of the reference sinusoidal signal for the actual sampling signal obtained at each sampling moment, including: The algorithm control module is used to determine the number of cycles m according to the preset frequency f; for the continuous m actual sampling signals obtained from the i-th to the i+m-1-th sampling moments, the j-th sample data of the reference sinusoidal signal is obtained; for the continuous m actual sampling signals obtained from the i+m-th to the i+2m-1-th sampling moments, the j+1-th sample data of the reference sinusoidal signal is obtained; wherein i, j and m are all positive integers, and 1≤j≤N, N is the number of sample data in one cycle of the reference sinusoidal signal; the relationship between f and m is 1 / f=m*N*t1; The algorithm control module is used to modulate the difference between the actual sampling signal and the reference sinusoidal signal according to the PID control algorithm to obtain an excitation signal, including: The algorithm control module is used to modulate the difference between the actual sampling signal obtained at each sampling moment and the sample data corresponding to the actual sampling signal according to the PID control algorithm to obtain an excitation signal with a frequency of the preset frequency f.

14. An electronic device, characterized in that: The electronic device comprises: Memory for storing computer programs; A processor, configured to execute a computer program stored in the memory, and when the computer program is executed, implement the method described in any one of claims 1 to 4.

15. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, which, when executed, implement the method described in any one of claims 1 to 4.

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