Battery parameter measurement method, device, apparatus, medium, and program product

Abstract

The application relates to a battery parameter measurement method, device, equipment, medium and program product. The method comprises the following steps: acquiring an alternating current impedance spectrum of a proton exchange membrane fuel cell by using a floating ground measurement method of an electrochemical measuring instrument; fitting the impedance of an equivalent circuit with the alternating current impedance spectrum of the proton exchange membrane fuel cell to determine a target impedance of the equivalent circuit; and calculating the parameters of the battery according to target circuit parameters corresponding to the target impedance of the equivalent circuit. The method can acquire the complete alternating current impedance spectrum of the proton exchange membrane fuel cell, can avoid potential interference between the electrochemical measuring instrument and the proton exchange membrane fuel cell, and improves the accuracy of the proton exchange membrane fuel cell parameter measurement.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery parameter measurement method, device, equipment, medium and program product. BACKGROUND

[0002] A proton exchange membrane fuel cell (PEMFC) is a high-efficiency energy conversion power generation device that converts chemical energy in fuel and oxidants into electrical energy in an electrochemical reaction without a combustion process. The proton exchange membrane fuel cell has the characteristics of high efficiency and low emission, is a new energy source, and has a wide range of market applications. Among them, the proton exchange membrane fuel cell is mainly applied to automobile power systems.

[0003] The proton exchange membrane fuel cell is currently in a key development stage of reducing costs and improving battery life. Dynamic measurement of the battery to obtain internal parameter change information is a core technology for online evaluation of the battery.

[0004] Currently, electrochemical impedance spectroscopy (EIS) technology is often used. An electrochemical measurement instrument applies an alternating current disturbance signal continuously changing from high frequency to low frequency to the proton exchange membrane fuel cell, and obtains various parameter information of the proton exchange membrane fuel cell by parameter fitting of the response signal.

[0005] However, the current electrochemical measurement cannot obtain complete electrochemical impedance spectroscopy information of the proton exchange membrane fuel cell, and the measurement instrument is prone to potential interference with the proton exchange membrane fuel cell, resulting in inaccurate measurement results of the proton exchange membrane fuel cell. SUMMARY

[0006] The present application provides a battery parameter measurement method, device, equipment, medium and program product, which can measure the parameters of the proton exchange membrane fuel cell based on complete electrochemical impedance spectroscopy information of the proton exchange membrane fuel cell, and improve the accuracy of the proton exchange membrane fuel cell parameter measurement.

[0007] In a first aspect, the present application provides a battery parameter measurement method applied to a proton exchange membrane fuel cell. The method comprises:

[0008] obtaining electrochemical impedance spectroscopy of the proton exchange membrane fuel cell by using a floating ground measurement method of an electrochemical measurement instrument;

[0009] The impedance of the equivalent circuit is fitted with the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit;

[0010] The parameters of the cell are calculated according to the target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0011] In one of the embodiments, the impedance of the equivalent circuit is fitted with the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit, including: calculating the initial impedance of the equivalent circuit according to the initial parameters of the equivalent circuit; fitting the initial impedance of the equivalent circuit and the AC impedance spectrum to obtain a fitting result satisfying a preset fitting condition, and determining the target impedance of the equivalent circuit according to the fitting result satisfying the preset fitting condition.

[0012] In one of the embodiments, the equivalent circuit includes a first measurement circuit, a second measurement circuit, a third measurement circuit and a constant phase angle element, the second measurement circuit and the third measurement circuit are connected in parallel, the second measurement circuit and the constant phase angle element are connected in parallel, and the first measurement circuit and the second measurement circuit are connected in series; the first measurement circuit includes a first resistor, the second measurement circuit includes a second resistor, and the third measurement circuit includes a third resistor and an inductor; wherein the third resistor and the inductor are connected in series; the initial impedance of the equivalent circuit is calculated according to the initial parameters of the equivalent circuit, including: calculating the initial impedance of the equivalent circuit according to the initial resistance value of the first resistor, the initial resistance value of the second resistor, the initial resistance value of the third resistor and the initial inductance value of the inductor, and the initial value of the constant phase angle element.

[0013] In one of the embodiments, the initial impedance of the equivalent circuit and the AC impedance spectrum are fitted to obtain a fitting result satisfying a preset fitting condition, and the target impedance of the equivalent circuit is determined according to the fitting result satisfying the preset fitting condition, including: fitting the initial impedance of the equivalent circuit and the AC impedance spectrum to obtain an initial fitting result; adjusting the initial parameters of the equivalent circuit according to the initial fitting result to generate adjusted parameters; taking the adjusted parameters as new initial parameters of the equivalent circuit to perform iterative calculation to generate new impedance of the equivalent circuit, until the new impedance of the equivalent circuit and the AC impedance spectrum are fitted to obtain a fitting result satisfying the preset fitting condition; taking the new impedance of the equivalent circuit corresponding to the fitting result satisfying the preset fitting condition as the target impedance of the equivalent circuit.

[0014] In one of the embodiments, the parameters of the battery are calculated according to target circuit parameters corresponding to the target impedance of the equivalent circuit, including: obtaining the target circuit parameters corresponding to the target impedance of the equivalent circuit; the target circuit parameters include a target resistance value of the first resistance, a target resistance value of the second resistance, a target resistance value of the third resistance, and a target inductance value of the inductance; calculating the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell according to the target resistance value of the first resistance; taking the target resistance value of the second resistance as the cathode polarization resistance of the proton exchange membrane fuel cell; and calculating the water balance parameter of the proton exchange membrane fuel cell according to the target resistance value of the third resistance and the target inductance value of the inductance.

[0015] In one of the embodiments, the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell is calculated according to the target resistance value of the first resistance, including: taking the target resistance value of the first resistance as the membrane resistance of the proton exchange membrane in the proton exchange membrane fuel cell; determining the conductivity of the proton exchange membrane according to the membrane resistance of the proton exchange membrane; and determining the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell according to the conductivity of the proton exchange membrane and the corresponding relationship between the conductivity of the proton exchange membrane and the water balance parameter of the proton exchange membrane.

[0016] In a second aspect, the application further provides a battery parameter measurement device. The device includes:

[0017] The acquisition module is configured to acquire the AC impedance spectrum of the proton exchange membrane fuel cell by using a floating ground measurement method of an electrochemical measurement instrument.

[0018] The determination module is configured to fit the impedance of the equivalent circuit with the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit.

[0019] The calculation module is configured to calculate the parameters of the battery according to target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0020] In a third aspect, the application further provides a computer device. The computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0021] The AC impedance spectrum of the proton exchange membrane fuel cell is acquired by using a floating ground measurement method of an electrochemical measurement instrument.

[0022] The impedance of the equivalent circuit is fitted with the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit.

[0023] The parameters of the battery are calculated according to target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0024] In a fourth aspect, the present application also provides a computer readable storage medium. The computer readable storage medium has a computer program stored thereon, and the computer program, when executed by a processor, implements the following steps:

[0025] An AC impedance spectrum of the proton exchange membrane fuel cell is obtained by using a floating ground measurement method through an electrochemical measuring instrument;

[0026] The impedance of the equivalent circuit is fitted with the AC impedance spectrum of the proton exchange membrane fuel cell to determine a target impedance of the equivalent circuit;

[0027] The parameters of the cell are calculated according to target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0028] In a fifth aspect, the present application also provides a computer program product. The computer program product comprises a computer program, and the computer program, when executed by a processor, implements the following steps:

[0029] An AC impedance spectrum of the proton exchange membrane fuel cell is obtained by using a floating ground measurement method through an electrochemical measuring instrument;

[0030] The impedance of the equivalent circuit is fitted with the AC impedance spectrum of the proton exchange membrane fuel cell to determine a target impedance of the equivalent circuit;

[0031] The parameters of the cell are calculated according to target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0032] The present application provides a battery parameter measurement method, device, equipment, medium and program product, which can obtain an AC impedance spectrum of a proton exchange membrane fuel cell by using a floating ground measurement method through an electrochemical measuring instrument, so that the electrochemical measuring instrument can not only obtain an AC impedance spectrum of the proton exchange membrane fuel cell in the first quadrant, but also obtain an AC impedance spectrum in the fourth quadrant containing low-frequency information of the proton exchange membrane fuel cell, that is, obtain a complete AC impedance spectrum of the proton exchange membrane fuel cell. Furthermore, the parameters of the proton exchange membrane fuel cell are measured based on the complete AC impedance spectrum of the proton exchange membrane fuel cell, which improves the accuracy of the proton exchange membrane fuel cell parameter measurement. At the same time, the floating ground measurement method makes the ground wire of the electrochemical measuring instrument not connected to the ground, and the proton exchange membrane fuel cell is not grounded, which avoids the formation of a loop between the electrochemical measuring instrument and the proton exchange membrane fuel cell and the ground, thereby avoiding potential interference between the electrochemical measuring instrument and the proton exchange membrane fuel cell, and further improving the accuracy of the proton exchange membrane fuel cell parameter measurement. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 An application environment diagram of a battery parameter measurement method in an embodiment;

[0034] Figure 2 Flowchart of a battery parameter measurement method in an embodiment;

[0035] Figure 3 Schematic diagram of a measurement circuit of AC impedance spectrum in an embodiment;

[0036] Figure 4 Schematic diagram of AC impedance spectrum of a proton exchange membrane fuel cell at different potentials in an embodiment using floating ground measurement method;

[0037] Figure 5 Schematic diagram of AC impedance spectrum of a proton exchange membrane fuel cell in an embodiment without using floating ground measurement method;

[0038] Figure 6 Another flowchart of a battery parameter measurement method in an embodiment;

[0039] Figure 7 Another flowchart of a battery parameter measurement method in an embodiment;

[0040] Figure 8 Schematic diagram of an equivalent circuit of a proton exchange membrane fuel cell in an embodiment;

[0041] Figure 9 Another flowchart of a battery parameter measurement method in an embodiment;

[0042] Figure 10 Another flowchart of a battery parameter measurement method in an embodiment;

[0043] Figure 11 Another schematic diagram of an equivalent circuit of a proton exchange membrane fuel cell in an embodiment;

[0044] Figure 12 Structural block diagram of a battery parameter measurement device in an embodiment;

[0045] Figure 13 Internal structural diagram of a computer device in an embodiment. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application is further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0047] The battery parameter measurement method provided by the embodiments of the present application can be applied to, for example, Figure 1The application environment is shown. Among them, the electrochemical measuring instrument 104 is used to measure the alternating current impedance spectrum of the proton exchange membrane fuel cell; the terminal 102 can be various personal computers, notebook computers, smart phones, tablet computers and the like, but is not limited to, used to analyze the alternating current impedance spectrum of the proton exchange membrane fuel cell, and determine the parameters of the proton exchange membrane fuel cell. Among them, the terminal 102 can communicate with the electrochemical measuring instrument 104 in a wired and wireless manner.

[0048] The proton exchange membrane fuel cell is currently facing a key development stage of reducing cost and improving battery life. Dynamic measurement of the battery and acquisition of internal parameter change information of the battery are core technologies for completing online evaluation of the battery.

[0049] At present, the electrochemical impedance spectroscopy (EIS) technology is often used. The electrochemical measuring instrument applies an alternating current disturbance signal continuously changing from high frequency to low frequency to the proton exchange membrane fuel cell, and obtains various parameter information of the proton exchange membrane fuel cell by parameter fitting of the obtained alternating current impedance spectrum.

[0050] However, the current electrochemical measuring instrument can only obtain the first quadrant alternating current impedance spectrum of the proton exchange membrane fuel cell, and lacks low frequency information of the proton exchange membrane fuel cell. Moreover, as an electrical device, the electrochemical measuring instrument is easy to cause potential interference between the proton exchange membrane fuel cell, thereby causing the problem of inaccurate measurement results of the proton exchange membrane fuel cell parameters.

[0051] In one embodiment, as Figure 2 shown, a battery parameter measurement method is provided. The method is applied to the terminal in Figure 1 for example, and specifically includes the following steps:

[0052] S201, using the floating ground measurement method of the electrochemical measuring instrument, obtaining the alternating current impedance spectrum of the proton exchange membrane fuel cell.

[0053] Among them, the electrochemical measuring instrument is an electrochemical measuring instrument supporting the floating ground measurement mode.

[0054] In a specific implementation, a circuit for measuring the alternating current impedance spectrum of the proton exchange membrane fuel cell can be constructed first, as Figure 3As shown, the circuit can include an electrochemical measuring instrument, a proton exchange membrane fuel cell, and a load, so that the proton exchange membrane fuel cell is in a discharging state in the circuit. After the circuit is built, the floating ground measurement unit of the electrochemical measuring instrument can be started, and the AC impedance spectrum of the proton exchange membrane fuel cell is obtained by using the floating ground measurement method. Wherein, e-load is the load, Fuel cell is the proton exchange membrane fuel cell, and S is the electrochemical measuring instrument.

[0055] In a possible implementation, as the proton exchange membrane fuel cell is continuously discharged, the potential of the proton exchange membrane fuel cell is continuously reduced, and the electrochemical measuring instrument can obtain the AC impedance spectrum of the proton exchange membrane fuel cell at different potentials respectively.

[0056] S202, fitting the impedance of the equivalent circuit of the proton exchange membrane fuel cell with the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit.

[0057] In a specific implementation, the multiple impedances of the equivalent circuit of the proton exchange membrane fuel cell under the AC disturbance signals of different frequencies can be calculated first, and then it is judged whether the multiple impedances corresponding to the equivalent circuit are located on the AC impedance spectrum of the proton exchange membrane fuel cell or are located near the curve of the AC impedance spectrum of the proton exchange membrane fuel cell, and the multiple impedances located on the AC impedance spectrum or near the curve of the AC impedance spectrum are determined as the target impedance of the equivalent circuit.

[0058] For example, the distances between the multiple impedances of the equivalent circuit under the AC disturbance signals of different frequencies and the impedances at the corresponding positions of the AC impedance spectrum of the proton exchange membrane fuel cell can be calculated, and the multiple impedances corresponding to the equivalent circuit with the minimum sum of distances or the minimum average distance of the multiple impedances can be determined as the target impedance of the equivalent circuit. Wherein, the impedance at the corresponding position of the AC impedance spectrum of the multiple impedances of the equivalent circuit refers to the impedance at the corresponding frequency of the AC impedance spectrum of the proton exchange membrane fuel cell. For example, if the impedance of the equivalent circuit under the AC disturbance signal of 1000 Hz is Z, the impedance at the corresponding position of the AC impedance spectrum is the impedance at the frequency of 1000 Hz on the AC impedance spectrum.

[0059] In a possible implementation manner, the multiple impedances of the equivalent circuit of the proton exchange membrane fuel cell under the AC disturbance signals of different frequencies can be calculated first, and then the multiple impedances corresponding to the equivalent circuit are subjected to EIS curve fitting to obtain an AC impedance spectrum corresponding to the equivalent circuit. Then, the AC impedance spectrum corresponding to the equivalent circuit and the AC impedance spectrum of the proton exchange membrane fuel cell obtained by the electrochemical measuring instrument by using the floating ground measurement method are subjected to difference minimization processing, and the AC impedance spectrum of the equivalent circuit that is least different from the AC impedance spectrum of the proton exchange membrane fuel cell is determined as a target AC impedance spectrum of the equivalent circuit, and the impedance of the equivalent circuit corresponding to the target AC impedance spectrum of the equivalent circuit is determined as a target impedance of the equivalent circuit.

[0060] S203, calculating the parameters of the battery according to the target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0061] The target circuit parameters corresponding to the target impedance of the equivalent circuit are parameters of each component in the equivalent circuit when the impedance of the equivalent circuit is the target impedance, for example, a resistance value of a resistor, a capacitance value of a capacitor, an inductance value of an inductor, and the like.

[0062] In a specific implementation, the parameters of each component of the equivalent circuit corresponding to the target impedance of the equivalent circuit can be determined as the target circuit parameters of the equivalent circuit, and then the parameters of the proton exchange membrane fuel cell are calculated based on the relationship between the target circuit parameters and the parameters of the proton exchange membrane fuel cell.

[0063] In a possible implementation manner, the EIS fitting software such as Zview and ZsimpWin can be used to fit the AC impedance spectrum of the equivalent circuit and the proton exchange membrane fuel cell, the parameters of each component of the equivalent circuit are changed to minimize the weighted total deviation of the impedance of the equivalent circuit under the AC disturbance signals of different frequencies, and then the parameters of each component of the equivalent circuit and the fitting error when the deviation is minimized are output. The parameters of each component of the equivalent circuit when the deviation is minimized are the target circuit parameters of the equivalent circuit, and the fitting error is the minimum weighted total deviation.

[0064] As shown in FIG. 6, Figure 4 As shown in FIG. 6, Figure 4 The AC impedance spectrum of the proton exchange membrane fuel cell under different potentials is obtained by the electrochemical measuring instrument by using the floating ground measurement method. The abscissa represents the real part resistance of the proton exchange membrane fuel cell, and the ordinate represents the imaginary part resistance of the proton exchange membrane fuel cell. The points at different frequencies on the AC impedance spectrum are the target impedances of the equivalent circuit under the AC disturbance signals of different frequencies obtained by fitting the equivalent circuit and the AC impedance spectrum, and the parameters of each component of the equivalent circuit corresponding to the target impedances are the target circuit parameters of the equivalent circuit.

[0065] It should be noted that, Figure 4 The AC impedance spectrum in the first quadrant and the fourth quadrant of the proton exchange membrane fuel cell. As shown in Figure 5 , Figure 5 The AC impedance spectrum of the proton exchange membrane fuel cell obtained by the electrochemical measuring instrument without using the floating ground measurement method is only the AC impedance spectrum in the first quadrant, lacking the AC impedance spectrum in the fourth quadrant, that is, lacking the impedance information of the proton exchange membrane fuel cell under low-frequency AC disturbance signal, so that the obtained impedance information of the proton exchange membrane fuel cell is incomplete. Further, the accuracy of the parameters of the proton exchange membrane fuel cell determined based on the incomplete information is low.

[0066] The battery parameter measurement method provided in the present application can obtain the AC impedance spectrum of the proton exchange membrane fuel cell by the electrochemical measuring instrument using the floating ground measurement method, so that the electrochemical measuring instrument can not only obtain the AC impedance spectrum of the proton exchange membrane fuel cell in the first quadrant, but also obtain the AC impedance spectrum in the fourth quadrant containing the low-frequency information of the proton exchange membrane fuel cell, that is, obtain the complete AC impedance spectrum of the proton exchange membrane fuel cell. Further, based on the complete AC impedance spectrum of the proton exchange membrane fuel cell, the parameters of the proton exchange membrane fuel cell are measured, which improves the accuracy of the parameter measurement of the proton exchange membrane fuel cell. At the same time, using the floating ground measurement method makes the ground of the electrochemical measuring instrument not connected to the ground, and the proton exchange membrane fuel cell is not grounded, avoiding the formation of a loop between the electrochemical measuring instrument and the proton exchange membrane fuel cell and the ground, thereby avoiding the potential interference between the electrochemical measuring instrument and the proton exchange membrane fuel cell, and further improving the accuracy of the parameter measurement of the proton exchange membrane fuel cell.

[0067] The foregoing embodiments introduce the scheme of fitting the impedance of the equivalent circuit and the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit. In another embodiment of the present application, the target impedance of the equivalent circuit can be determined according to the fitting result meeting the preset fitting condition. For example, the foregoing "fitting the impedance of the equivalent circuit of the proton exchange membrane fuel cell and the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit" specifically includes the steps as shown in Figure 6 .

[0068] S601, calculating the initial impedance of the equivalent circuit according to the initial parameters of the equivalent circuit.

[0069] S602, fitting the initial impedance of the equivalent circuit and the AC impedance spectrum to obtain a fitting result meeting the preset fitting condition, and determining the target impedance of the equivalent circuit according to the fitting result meeting the preset fitting condition.

[0070] In specific implementations, before fitting the equivalent circuit and the AC impedance spectrum, initial parameters of each component in the equivalent circuit can be calculated to obtain an initial impedance of the equivalent circuit. Then, the initial impedance of the equivalent circuit and the AC impedance spectrum are fitted to determine a fitting result (for example, a fitting error between the initial impedance of the equivalent circuit and the AC impedance spectrum) of the initial impedance of the equivalent circuit and the AC impedance spectrum, and whether the fitting result meets a preset fitting condition is determined. If the fitting result meets the preset fitting condition, the initial impedance of the equivalent circuit is the target impedance of the equivalent circuit. If the fitting result does not meet the preset fitting condition, the parameters of each component of the equivalent circuit are changed so that the fitting result of the impedance of the equivalent circuit and the AC impedance spectrum meets the preset fitting condition, and the impedance of the equivalent circuit that meets the preset fitting condition is the target impedance of the equivalent circuit.

[0071] In the above process, changing the parameters of each component of the equivalent circuit so that the fitting result of the impedance of the equivalent circuit and the AC impedance spectrum meets the preset fitting condition can include changing the parameters of each component of the equivalent circuit multiple times and gradually adjusting the impedance of the equivalent circuit, so that the fitting result of the impedance of the equivalent circuit and the AC impedance spectrum meets the preset fitting condition. That is, the step S602 can include the steps as shown in Figure 7

[0072] S701, fitting the initial impedance of the equivalent circuit and the AC impedance spectrum to obtain an initial fitting result.

[0073] S702, adjusting the initial parameters of the equivalent circuit according to the initial fitting result to generate adjusted parameters.

[0074] S703, iteratively calculating the adjusted parameters as new initial parameters of the equivalent circuit to generate a new impedance of the equivalent circuit, until the new impedance of the equivalent circuit and the AC impedance spectrum are fitted to obtain a fitting result that meets the preset fitting condition.

[0075] S704, taking the new impedance of the equivalent circuit corresponding to the fitting result that meets the preset fitting condition as the target impedance of the equivalent circuit.

[0076] In specific implementations, before fitting the equivalent circuit and the AC impedance spectrum, initial parameters of each component in the equivalent circuit can be calculated to obtain an initial impedance of the equivalent circuit. Then, the initial impedance of the equivalent circuit and the AC impedance spectrum are fitted to determine an initial fitting result (for example, a fitting error between the initial impedance of the equivalent circuit and the AC impedance spectrum) of the initial impedance of the equivalent circuit and the AC impedance spectrum, and whether the initial fitting result meets a preset fitting condition (for example, the fitting error is less than 3%) is determined. If the initial fitting result meets the preset fitting condition, the initial impedance of the equivalent circuit is the target impedance of the equivalent circuit. ​

[0077] If the initial fitting result does not satisfy the preset fitting condition, the initial parameters of the equivalent circuit are adjusted according to the difference between the initial fitting result and the preset fitting condition, and the new impedance of the equivalent circuit is calculated based on the adjusted initial parameters of the equivalent circuit. Then the new impedance of the equivalent circuit and the AC impedance spectrum are fitted to obtain a new fitting result, and the new fitting result and the preset fitting condition are judged. If the new fitting result satisfies the preset fitting condition, the new impedance of the equivalent circuit is the target impedance of the equivalent circuit. If the new fitting result does not satisfy the preset fitting condition, the equivalent circuit is further adjusted according to the difference between the new fitting result and the preset fitting condition until the fitting result of the impedance of the equivalent circuit and the AC impedance spectrum satisfies the preset fitting condition, and the impedance of the equivalent circuit that satisfies the preset fitting condition is determined as the target impedance of the equivalent circuit.

[0078] The embodiments of the present application provide a scheme for determining the target impedance of the equivalent circuit according to the fitting result of the impedance of the equivalent circuit and the AC impedance spectrum. Specifically, the initial impedance of the equivalent circuit and the AC impedance spectrum can be fitted first, and then it is judged whether the fitting result satisfies the preset fitting condition. If the fitting result does not satisfy the preset fitting condition, the parameters of the equivalent circuit are adjusted, and the adjusted parameters of the equivalent circuit are iteratively calculated to obtain the new impedance of the equivalent circuit until the fitting result of the new impedance of the equivalent circuit and the AC impedance spectrum satisfies the preset fitting condition, and the impedance of the equivalent circuit that satisfies the preset fitting condition is determined as the target impedance of the equivalent circuit. It can be seen that the equivalent circuit can be adjusted multiple times according to the fitting result in the process of determining the target impedance of the equivalent circuit until the fitting result satisfies the preset fitting condition, which improves the accuracy of the determined target impedance of the equivalent circuit, and further, the calculated parameters of the battery based on the target circuit parameters corresponding to the accurate target impedance are also more accurate.

[0079] The foregoing embodiments introduce the schemes related to the equivalent circuit of the proton exchange membrane fuel cell, such as calculating the initial impedance of the equivalent circuit according to the initial parameters of the equivalent circuit, calculating the parameters of the battery according to the target circuit parameters of the equivalent circuit, etc. In another embodiment of the present application, the specific structure of the equivalent circuit can be specifically set according to the parameters of the proton exchange membrane fuel cell that need to be measured. For example, as shown in FIG. 1, the equivalent circuit of the proton exchange membrane fuel cell provided in the embodiments of the present application specifically includes: Figure 8 Figure 8 The equivalent circuit diagram of the proton exchange membrane fuel cell provided in the embodiments of the present application specifically includes:

[0080] The first measurement circuit, the second measurement circuit, the third measurement circuit and the constant phase angle element are connected in parallel, the second measurement circuit and the constant phase angle element are connected in parallel, and the first measurement circuit and the second measurement circuit are connected in series.

[0081] ​The first measurement circuit includes a first resistor, the second measurement circuit includes a second resistor, and the third measurement circuit includes a third resistor and an inductor.

[0082] According to initial parameters of the equivalent circuit, an initial impedance of the equivalent circuit is calculated, including:

[0083] According to initial resistance values of the first resistor, the second resistor, and the third resistor, and an initial inductance value of the inductor, and an initial value of the constant phase element, the initial impedance of the equivalent circuit is calculated.

[0084] The equivalent circuit of the proton exchange membrane fuel cell provided in the embodiments of the present application includes a first measurement circuit, a second measurement circuit, a third measurement circuit, and a constant phase element CPE; the first measurement circuit includes a first resistor R0, the second measurement circuit includes a second resistor R1, and the third measurement circuit includes a third resistor R3 and an inductor L. The first measurement circuit, the second measurement circuit, and the third measurement circuit are respectively used to measure different parameters of the proton exchange membrane fuel cell.

[0085] The first resistor and the second resistor are connected in series, the constant phase element and the second resistor are connected in parallel, and the third resistor and the inductor are connected in series and then connected in parallel with the second resistor.

[0086] Based on the equivalent circuit provided in the embodiments of the present application, when the initial impedance of the equivalent circuit is calculated according to initial parameters of the equivalent circuit, initial resistance values of the first resistor, the second resistor, and the third resistor, and an initial inductance value of the inductor, and an initial value of the constant phase element are calculated, so as to obtain the initial impedance of the equivalent circuit.

[0087] Based on the equivalent circuit provided in the embodiments of the present application, when the parameters of the proton exchange membrane fuel cell are calculated according to target circuit parameters corresponding to a target impedance of the equivalent circuit, the steps shown in the following table are specifically included: Figure 9

[0088] S901, target circuit parameters corresponding to a target impedance of the equivalent circuit are obtained; the target circuit parameters include a target resistance value of the first resistor, a target resistance value of the second resistor, a target resistance value of the third resistor, and a target inductance value of the inductor.

[0089] ​In the specific implementation, the initial impedance of the equivalent circuit and the AC impedance spectrum of the proton exchange membrane fuel cell provided in the embodiment of the application can be fitted first, and the parameters of each component of the equivalent circuit are adjusted according to the fitting result until the fitting result of the impedance of the equivalent circuit and the AC impedance spectrum meets the preset fitting condition, then the impedance of the equivalent circuit meeting the preset fitting condition is determined as the target impedance of the equivalent circuit, and the parameters of each component of the equivalent circuit when the impedance of the equivalent circuit is the target impedance are determined as the target circuit parameters of the equivalent circuit. The target circuit parameters of the equivalent circuit include the target resistance value of the first resistor in the first measurement module, the target resistance value of the second resistor in the second measurement module, the target resistance value of the third resistor in the third measurement module, and the target inductance value of the inductor.

[0090] S902, according to the target resistance value of the first resistor, calculating the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell.

[0091] The first measurement module is used to measure the water balance parameter of the proton exchange membrane of the proton exchange membrane fuel cell.

[0092] In the specific implementation, the resistance value of the first resistor can be calculated according to the relationship between the target resistance value of the first resistor in the first measurement module and the water content of the proton exchange membrane, so as to obtain the water content of the proton exchange membrane, that is, the water balance parameter of the proton exchange membrane. Specifically, the process of calculating the water content of the proton exchange membrane according to the target resistance value of the first resistor can include the steps as shown in Figure 10

[0093] S1001, taking the target resistance value of the first resistor as the membrane resistance of the proton exchange membrane in the proton exchange membrane fuel cell.

[0094] S1002, determining the conductivity of the proton exchange membrane according to the membrane resistance of the proton exchange membrane.

[0095] S1003, determining the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell according to the conductivity of the proton exchange membrane, and the corresponding relationship between the conductivity of the proton exchange membrane and the water balance parameter of the proton exchange membrane.

[0096] In the specific implementation, the target resistance value of the first resistor is the membrane resistance of the proton exchange membrane of the proton exchange membrane fuel cell, and the conductivity of the proton exchange membrane is determined according to the relationship between the membrane resistance of the proton exchange membrane and the conductivity of the proton exchange membrane, that is, the following formula (1).

[0097]

[0098] wherein σ represents the conductivity of the proton exchange membrane; d represents the length of the proton exchange membrane; w represents the width of the proton exchange membrane; and t represents the thickness of the proton exchange membrane.​

[0099] Then, based on the conductivity of the proton exchange membrane, the water content of the proton exchange membrane is determined according to a linear relationship between the conductivity of the proton exchange membrane and the water content of the proton exchange membrane, that is, the water balance parameter of the proton exchange membrane.

[0100] S903, the target resistance value of the second resistance is determined as the cathode polarization resistance of the proton exchange membrane fuel cell.

[0101] The second measurement module is used to measure the cathode polarization resistance of the proton exchange membrane fuel cell.

[0102] In a specific implementation, the target resistance value of the second resistance in the second measurement module can be determined as the cathode polarization resistance of the proton exchange membrane fuel cell.

[0103] S904, the water balance parameter of the proton exchange membrane fuel cell is calculated according to the target resistance value of the third resistance and the target inductance value of the inductance.

[0104] The third measurement module is used to measure the water balance parameter of the proton exchange membrane fuel cell.

[0105] In a specific implementation, the target resistance value of the third resistance and the target inductance value of the inductance can be calculated according to the relationship between the target resistance value of the third resistance, the target inductance value of the inductance and the water content of the proton exchange membrane fuel cell, so as to obtain the water content of the proton exchange membrane fuel cell, that is, the water balance parameter of the proton exchange membrane fuel cell.

[0106] It should be noted that the above embodiments only illustrate the parameter measurement process of the proton exchange membrane fuel cell at one potential, and if the parameters of the proton exchange membrane fuel cell at different potentials are measured respectively, the change of the parameters of the proton exchange membrane fuel cell with the potential can be obtained, that is, the dynamic parameters of the proton exchange membrane fuel cell. For example, the water content of the proton exchange membrane fuel cell at 0.8V, 0.7V, 0.6V, 0.5V, 0.4V, 0.3V can be calculated respectively, and then the change of the water content of the proton exchange membrane fuel cell with the potential, that is, the dynamic water content of the proton exchange membrane fuel cell, can be determined according to the six water contents calculated above.

[0107] The equivalent circuit provided in the embodiments of the present application comprises three measurement modules, i.e., a first measurement circuit, a second measurement circuit and a third measurement circuit, and the three measurement modules are respectively used to measure three different parameters of the proton exchange membrane fuel cell. The first measurement circuit is used to measure the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell, the second measurement circuit is used to measure the cathode polarization resistance of the proton exchange membrane fuel cell, and the third measurement circuit is used to measure the water balance parameter of the proton exchange membrane fuel cell. It can be seen that the physical meaning of each component in the equivalent circuit provided in the present application is clear.

[0108] As Figure 11 shown, Figure 11 is an existing equivalent circuit, including a first resistor R1, a capacitor C1, a second resistor R2, a constant phase element CPE1, a third resistor R3, a constant phase element CPE2, and a fourth resistor R4. Based on Figure 11 the equivalent circuit shown, the parameters of the proton exchange membrane fuel cell can be measured, but the physical meaning of each component in the equivalent circuit is not clear, and the parameters of the proton exchange membrane fuel cell measured by each component are not clear. Compared with Figure 11 the existing equivalent circuit shown, the equivalent circuit provided by the present application has a clear physical meaning, and the parameters of the proton exchange membrane fuel cell corresponding to one or more specific components in the equivalent circuit are clear, which is easy for the measurement of the parameters of the proton exchange membrane fuel cell and improves the accuracy of the measurement of the parameters of the proton exchange membrane fuel cell.

[0109] It should be understood that, although each step in the flowchart involved in each embodiment as described above is displayed in sequence according to the arrow, these steps are not necessarily executed in sequence according to the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least part of the steps in the flowchart involved in each embodiment as described above can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or steps or stages in other steps.

[0110] Based on the same inventive concept, the present application also provides a battery parameter measurement device for implementing the above-mentioned battery parameter measurement method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more battery parameter measurement device embodiments provided below can refer to the limitations of the battery parameter measurement method described above, and will not be repeated here.

[0111] In one embodiment, as Figure 12 shown, a battery parameter measurement device is provided, comprising: an acquisition module, a determination module and a calculation module, wherein:

[0112] The acquisition module 1201 is configured to acquire the AC impedance spectrum of the proton exchange membrane fuel cell by using the floating ground measurement method of the electrochemical measurement instrument.

[0113] The determining module 1202 is configured to fit the impedance of the equivalent circuit of the proton exchange membrane fuel cell with the AC impedance spectrum of the proton exchange membrane fuel cell to determine a target impedance of the equivalent circuit.

[0114] The calculating module 1203 is configured to calculate the parameters of the cell according to target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0115] In an embodiment, based on the above-mentioned embodiment, the determining module 1202 is specifically configured to calculate an initial impedance of the equivalent circuit according to the initial parameters of the equivalent circuit; fit the initial impedance of the equivalent circuit with the AC impedance spectrum to obtain a fitting result meeting a preset fitting condition, and determine the target impedance of the equivalent circuit according to the fitting result meeting the preset fitting condition.

[0116] In an embodiment, based on the above-mentioned embodiment, the equivalent circuit includes a first measurement circuit, a second measurement circuit, a third measurement circuit and a constant phase angle element, the second measurement circuit and the third measurement circuit are connected in parallel, the second measurement circuit and the constant phase angle element are connected in parallel, and the first measurement circuit and the second measurement circuit are connected in series; the first measurement circuit includes a first resistor, the second measurement circuit includes a second resistor, the third measurement circuit includes a third resistor and an inductor; wherein the third resistor and the inductor are connected in series; the initial impedance of the equivalent circuit is calculated according to the initial resistance value of the first resistor, the initial resistance value of the second resistor, the initial resistance value of the third resistor, the initial inductance value of the inductor and the initial value of the constant phase angle element.

[0117] In an embodiment, based on the above-mentioned embodiment, the initial impedance of the equivalent circuit is fitted with the AC impedance spectrum to obtain an initial fitting result; the initial parameters of the equivalent circuit are adjusted according to the initial fitting result to generate adjusted parameters; the adjusted parameters are taken as new initial parameters of the equivalent circuit for iterative calculation to generate a new impedance of the equivalent circuit, until the new impedance of the equivalent circuit is fitted with the AC impedance spectrum to obtain a fitting result meeting a preset fitting condition; the new impedance of the equivalent circuit corresponding to the fitting result meeting the preset fitting condition is taken as the target impedance of the equivalent circuit.

[0118] In an embodiment, based on the above-mentioned embodiment, the target circuit parameters corresponding to the target impedance of the equivalent circuit are obtained; the target circuit parameters include a target resistance value of the first resistor, a target resistance value of the second resistor, a target resistance value of the third resistor and a target inductance value of the inductor; the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell is calculated according to the target resistance value of the first resistor; the target resistance value of the second resistor is taken as the cathode polarization resistance of the proton exchange membrane fuel cell; and the water balance parameter of the proton exchange membrane fuel cell is calculated according to the target resistance value of the third resistor and the target inductance value of the inductor.

[0119] In one embodiment, on the basis of the above-mentioned embodiments, the target resistance value of the first resistor is taken as the membrane resistance of the proton exchange membrane in the proton exchange membrane fuel cell; the conductivity of the proton exchange membrane is determined according to the membrane resistance of the proton exchange membrane; the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell is determined according to the conductivity of the proton exchange membrane and the corresponding relationship between the conductivity of the proton exchange membrane and the water balance parameter of the proton exchange membrane.

[0120] Each module in the above-mentioned battery parameter measurement device can be realized by software, hardware and a combination thereof in whole or in part. The above-mentioned modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so as to be called and executed by the processor to perform the operations corresponding to the above-mentioned modules.

[0121] In one embodiment, a computer device is provided, which can be a terminal, and the internal structure diagram thereof can be as shown in FIG. 1. The computer device includes a processor, a memory, a communication interface, a display screen and an input device connected through a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The communication interface of the computer device is used to perform wired or wireless communication with an external terminal. The wireless communication can be achieved by WIFI, mobile cellular network, NFC (near field communication) or other technologies. The computer program is executed by the processor to implement a battery parameter measurement method. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer overlaid on the display screen, or a key, trackball or touchpad arranged on the shell of the computer device, or an external keyboard, touchpad or mouse, etc. Figure 13 Those skilled in the art can understand that the structure shown in FIG. 1 is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0122] Figure 13 In one embodiment, a computer device is provided, which includes a memory and a processor. The memory stores a computer program. The processor executes the computer program to implement the following steps:

[0123] In one embodiment, a computer device is provided, which includes a memory and a processor. The memory stores a computer program. The processor executes the computer program to implement the following steps:

[0124] ​The electrochemical measuring instrument is used to obtain the AC impedance spectrum of the proton exchange membrane fuel cell by using the floating ground measurement method;

[0125] The impedance of the equivalent circuit of the proton exchange membrane fuel cell is fitted with the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit.

[0126] The parameters of the cell are calculated according to the target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0127] In one embodiment, the processor, when executing the computer program, also implements the following steps: calculating the initial impedance of the equivalent circuit according to the initial parameters of the equivalent circuit; fitting the initial impedance of the equivalent circuit with the AC impedance spectrum to obtain a fitting result that meets a preset fitting condition, and determining the target impedance of the equivalent circuit according to the fitting result that meets the preset fitting condition.

[0128] In one embodiment, the equivalent circuit includes a first measurement circuit, a second measurement circuit, a third measurement circuit, and a constant phase angle element, the second measurement circuit and the third measurement circuit are connected in parallel, the second measurement circuit and the constant phase angle element are connected in parallel, and the first measurement circuit and the second measurement circuit are connected in series; the first measurement circuit includes a first resistor, the second measurement circuit includes a second resistor, the third measurement circuit includes a third resistor and an inductor; wherein the third resistor and the inductor are connected in series; and the processor, when executing the computer program, also implements the following steps: calculating the initial impedance of the equivalent circuit according to the initial resistance value of the first resistor, the initial resistance value of the second resistor, the initial resistance value of the third resistor, the initial inductance value of the inductor, and the initial value of the constant phase angle element.

[0129] In one embodiment, the processor, when executing the computer program, also implements the following steps: fitting the initial impedance of the equivalent circuit with the AC impedance spectrum to obtain an initial fitting result; adjusting the initial parameters of the equivalent circuit according to the initial fitting result to generate adjusted parameters; iteratively calculating the new impedance of the equivalent circuit by using the adjusted parameters as new initial parameters of the equivalent circuit until a fitting result that meets a preset fitting condition is obtained by fitting the new impedance of the equivalent circuit with the AC impedance spectrum; and taking the new impedance of the equivalent circuit corresponding to the fitting result that meets the preset fitting condition as the target impedance of the equivalent circuit.

[0130] In one embodiment, the processor, when executing the computer program, further implements the following steps: obtaining target circuit parameters corresponding to the target impedance of the equivalent circuit; the target circuit parameters include a target resistance value of the first resistance, a target resistance value of the second resistance, a target resistance value of the third resistance, and a target inductance value of the inductance; calculating the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell according to the target resistance value of the first resistance; taking the target resistance value of the second resistance as the cathode polarization resistance of the proton exchange membrane fuel cell; and calculating the water balance parameter of the proton exchange membrane fuel cell according to the target resistance value of the third resistance and the target inductance value of the inductance.

[0131] In one embodiment, the processor, when executing the computer program, further implements the following steps: taking the target resistance value of the first resistance as the membrane resistance of the proton exchange membrane in the proton exchange membrane fuel cell; determining the conductivity of the proton exchange membrane according to the membrane resistance of the proton exchange membrane; and determining the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell according to the conductivity of the proton exchange membrane and the corresponding relationship between the conductivity of the proton exchange membrane and the water balance parameter of the proton exchange membrane.

[0132] In one embodiment, a computer readable storage medium is provided, and the computer readable storage medium stores a computer program. When the computer program is executed by a processor, the following steps are implemented:

[0133] An electrochemical measuring instrument is used to obtain an AC impedance spectrum of the proton exchange membrane fuel cell by using a floating ground measurement method;

[0134] The impedance of the equivalent circuit of the proton exchange membrane fuel cell is fitted with the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit;

[0135] The parameters of the battery are calculated according to the target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0136] In one embodiment, the processor, when executing the computer program, further implements the following steps: calculating the initial impedance of the equivalent circuit according to the initial parameters of the equivalent circuit; fitting the initial impedance of the equivalent circuit with the AC impedance spectrum to obtain a fitting result that meets a preset fitting condition, and determining the target impedance of the equivalent circuit according to the fitting result that meets the preset fitting condition. A battery parameter measurement method is characterized in that it is applied to a proton exchange membrane fuel cell, and the method comprises:

[0137] In one embodiment, the equivalent circuit includes a first measurement circuit, a second measurement circuit, a third measurement circuit and a constant phase angle element, the second measurement circuit and the third measurement circuit are connected in parallel, the second measurement circuit and the constant phase angle element are connected in parallel, and the first measurement circuit and the second measurement circuit are connected in series; the first measurement circuit includes a first resistor, the second measurement circuit includes a second resistor, and the third measurement circuit includes a third resistor and an inductor; wherein the third resistor and the inductor are connected in series; the computer program further implements the following steps when executed by the processor: calculating the initial impedance of the equivalent circuit according to the initial resistance value of the first resistor, the initial resistance value of the second resistor, the initial resistance value of the third resistor, the initial inductance value of the inductor, and the initial value of the constant phase angle element.

[0138] In one embodiment, the computer program further implements the following steps when executed by the processor: fitting the initial impedance of the equivalent circuit and the alternating current impedance spectrum to obtain an initial fitting result; adjusting the initial parameters of the equivalent circuit according to the initial fitting result to generate adjusted parameters; iteratively calculating the new impedance of the equivalent circuit by taking the adjusted parameters as new initial parameters of the equivalent circuit until the new impedance of the equivalent circuit and the alternating current impedance spectrum are fitted to obtain a fitting result that meets a preset fitting condition; taking the new impedance of the equivalent circuit corresponding to the fitting result that meets the preset fitting condition as the target impedance of the equivalent circuit.

[0139] In one embodiment, the computer program further implements the following steps when executed by the processor: obtaining target circuit parameters corresponding to the target impedance of the equivalent circuit; the target circuit parameters include a target resistance value of the first resistor, a target resistance value of the second resistor, a target resistance value of the third resistor, and a target inductance value of the inductor; calculating the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell according to the target resistance value of the first resistor; taking the target resistance value of the second resistor as the cathode polarization resistance of the proton exchange membrane fuel cell; and calculating the water balance parameter of the proton exchange membrane fuel cell according to the target resistance value of the third resistor and the target inductance value of the inductor.

[0140] In one embodiment, the computer program further implements the following steps when executed by the processor: taking the target resistance value of the first resistor as the membrane resistance of the proton exchange membrane in the proton exchange membrane fuel cell; determining the conductivity of the proton exchange membrane according to the membrane resistance of the proton exchange membrane; and determining the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell according to the conductivity of the proton exchange membrane, and the corresponding relationship between the conductivity of the proton exchange membrane and the water balance parameter of the proton exchange membrane.

[0141] In one embodiment, a computer program product is provided, including a computer program that implements the following steps when executed by a processor:

[0142] The AC impedance spectrum of the proton exchange membrane fuel cell is obtained by using a floating ground measurement method through an electrochemical measuring instrument;

[0143] The impedance of the equivalent circuit of the proton exchange membrane fuel cell is fitted with the AC impedance spectrum of the proton exchange membrane fuel cell to determine the target impedance of the equivalent circuit.

[0144] The parameters of the cell are calculated according to the target circuit parameters corresponding to the target impedance of the equivalent circuit.

[0145] In one embodiment, the computer program, when executed by the processor, further implements the following steps: calculating the initial impedance of the equivalent circuit according to the initial parameters of the equivalent circuit; fitting the initial impedance of the equivalent circuit with the AC impedance spectrum to obtain a fitting result that meets a preset fitting condition, and determining the target impedance of the equivalent circuit according to the fitting result that meets the preset fitting condition. A battery parameter measurement method is characterized in that it is applied to a proton exchange membrane fuel cell, and the method comprises:

[0146] In one embodiment, the equivalent circuit comprises a first measurement circuit, a second measurement circuit, a third measurement circuit, and a constant phase angle element, the second measurement circuit and the third measurement circuit are connected in parallel, the second measurement circuit and the constant phase angle element are connected in parallel, and the first measurement circuit and the second measurement circuit are connected in series; the first measurement circuit comprises a first resistor, the second measurement circuit comprises a second resistor, the third measurement circuit comprises a third resistor and an inductor; wherein the third resistor and the inductor are connected in series; the computer program, when executed by the processor, further implements the following steps: calculating the initial impedance of the equivalent circuit according to the initial resistance value of the first resistor, the initial resistance value of the second resistor, the initial resistance value of the third resistor, the initial inductance value of the inductor, and the initial value of the constant phase angle element.

[0147] In one embodiment, the computer program, when executed by the processor, further implements the following steps: fitting the initial impedance of the equivalent circuit with the AC impedance spectrum to obtain an initial fitting result; adjusting the initial parameters of the equivalent circuit according to the initial fitting result to generate adjusted parameters; iteratively calculating the new impedance of the equivalent circuit by taking the adjusted parameters as new initial parameters of the equivalent circuit until a fitting result that meets a preset fitting condition is obtained by fitting the new impedance of the equivalent circuit with the AC impedance spectrum; and taking the new impedance of the equivalent circuit corresponding to the fitting result that meets the preset fitting condition as the target impedance of the equivalent circuit.

[0148] In one embodiment, the computer program, when executed by the processor, further implements the following steps: obtaining a target circuit parameter corresponding to a target impedance of the equivalent circuit; the target circuit parameter comprises a target resistance value of the first resistance, a target resistance value of the second resistance, a target resistance value of the third resistance, and a target inductance value of the inductance; calculating the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell according to the target resistance value of the first resistance; taking the target resistance value of the second resistance as the cathode polarization resistance of the proton exchange membrane fuel cell; and calculating the water balance parameter of the proton exchange membrane fuel cell according to the target resistance value of the third resistance and the target inductance value of the inductance.

[0149] In one embodiment, the computer program, when executed by the processor, further implements the following steps: taking the target resistance value of the first resistance as the membrane resistance of the proton exchange membrane in the proton exchange membrane fuel cell; determining the conductivity of the proton exchange membrane according to the membrane resistance of the proton exchange membrane; and determining the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell according to the conductivity of the proton exchange membrane and the corresponding relationship between the conductivity of the proton exchange membrane and the water balance parameter of the proton exchange membrane.

[0150] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (Read-Only Memory, ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive memory (ReRAM), magnetoresistive random access memory (Magnetoresistive Random Access Memory, MRAM), ferroelectric memory (Ferroelectric Random Access Memory, FRAM), phase change memory (Phase Change Memory, PCM), graphene memory, etc. Volatile memory can include random access memory (Random Access Memory, RAM) or external cache memory, etc. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (Static Random Access Memory, SRAM) or dynamic random access memory (Dynamic Random Access Memory, DRAM), etc. The database involved in the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., without being limited thereto.

[0151] Any combination of the technical features of the above embodiments can be made. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0152] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method of measuring a parameter of a battery, the method comprising: The method is applied to a proton exchange membrane fuel cell, and comprises the following steps: An AC impedance spectrum of the proton exchange membrane fuel cell is obtained by using a floating ground measurement method of an electrochemical measuring instrument; Initial impedance of an equivalent circuit of the proton exchange membrane fuel cell is calculated according to initial parameters of the equivalent circuit; Initial fitting results are obtained by fitting the initial impedance of the equivalent circuit and the AC impedance spectrum of the proton exchange membrane fuel cell; The initial parameters of the equivalent circuit are adjusted according to the initial fitting results to generate adjusted parameters; The adjusted parameters are taken as new initial parameters of the equivalent circuit for iterative calculation to generate new impedance of the equivalent circuit until fitting results meeting preset fitting conditions are obtained by fitting the new impedance of the equivalent circuit and the AC impedance spectrum; The new impedance of the equivalent circuit corresponding to the fitting results meeting the preset fitting conditions is taken as target impedance of the equivalent circuit; Parameters of the fuel cell are calculated according to target circuit parameters corresponding to the target impedance of the equivalent circuit.

2. The method of claim 1, wherein, The equivalent circuit comprises a first measurement circuit, a second measurement circuit, a third measurement circuit and a constant phase angle element, the second measurement circuit and the third measurement circuit are connected in parallel, the second measurement circuit and the constant phase angle element are connected in parallel, and the first measurement circuit and the second measurement circuit are connected in series; The first measurement circuit comprises a first resistor, the second measurement circuit comprises a second resistor, and the third measurement circuit comprises a third resistor and an inductor; wherein the third resistor and the inductor are connected in series; The initial impedance of the equivalent circuit is calculated according to initial parameters of the equivalent circuit of the proton exchange membrane fuel cell, which comprises the following steps: The initial impedance of the equivalent circuit is calculated according to initial resistance values of the first resistor, the second resistor and the third resistor, an initial inductance value of the inductor and an initial value of the constant phase angle element.

3. The method of claim 2, wherein, The parameters of the fuel cell are calculated according to target circuit parameters corresponding to the target impedance of the equivalent circuit, which comprises the following steps: Target circuit parameters corresponding to the target impedance of the equivalent circuit are obtained; the target circuit parameters comprise a target resistance value of the first resistor, a target resistance value of the second resistor, a target resistance value of the third resistor and a target inductance value of the inductor; A water balance parameter of a proton exchange membrane in the proton exchange membrane fuel cell is calculated according to the target resistance value of the first resistor; The target resistance value of the second resistor is taken as a cathode polarization resistance of the proton exchange membrane fuel cell; A water balance parameter of the proton exchange membrane fuel cell is calculated according to the target resistance value of the third resistor and the target inductance value of the inductor.

4. The method of claim 3, wherein, The target resistance value of the first resistor is taken as a membrane resistance of the proton exchange membrane in the proton exchange membrane fuel cell; The conductivity of the proton exchange membrane is determined according to the membrane resistance of the proton exchange membrane. ​ According to the conductivity of the proton exchange membrane, the correspondence between the conductivity of the proton exchange membrane and the water balance parameter of the proton exchange membrane, the water balance parameter of the proton exchange membrane in the proton exchange membrane fuel cell is determined.

5. The method according to any one of claims 1 to 4, characterized in that, The floating ground measurement method is used by the electrochemical measuring instrument to obtain the AC impedance spectrum of the proton exchange membrane fuel cell, including: The floating ground measurement method is used by the electrochemical measuring instrument to obtain the AC impedance spectrum of the proton exchange membrane fuel cell at different potentials.

6. The method according to any one of claims 1 to 4, characterized in that, The AC impedance spectrum includes the first quadrant and the fourth quadrant of the AC impedance spectrum of the proton exchange membrane fuel cell.

7. A battery parameter measuring device, characterized by, The device is applied to a proton exchange membrane fuel cell, and the device includes: An acquisition module is configured to use the floating ground measurement method of the electrochemical measuring instrument to obtain the AC impedance spectrum of the proton exchange membrane fuel cell. A determination module is configured to calculate the initial impedance of the equivalent circuit according to the initial parameters of the equivalent circuit of the proton exchange membrane fuel cell; perform fitting on the initial impedance of the equivalent circuit and the AC impedance spectrum of the proton exchange membrane fuel cell to obtain an initial fitting result; adjust the initial parameters of the equivalent circuit according to the initial fitting result to generate adjusted parameters; perform iterative calculation on the adjusted parameters as new initial parameters of the equivalent circuit to generate new impedance of the equivalent circuit until fitting is performed on the new impedance of the equivalent circuit and the AC impedance spectrum to obtain a fitting result that meets a preset fitting condition; and take the new impedance of the equivalent circuit corresponding to the fitting result that meets the preset fitting condition as target impedance of the equivalent circuit. A calculation module is configured to calculate the parameters of the fuel cell according to target circuit parameters corresponding to the target impedance of the equivalent circuit.

8. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that, The processor executes the computer program to implement the steps of the method of any one of claims 1 to 6.

9. A computer readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 6.

10. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 6. The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 6.

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