TWI836990B - Impedance measuring device and method for measuring interfacial contact resistance - Google Patents

Abstract

The present invention discloses an impedance measuring device, comprising: a first fixture comprising a first upper clamp and a first lower clamp; a second fixture comprising a second upper clamp and a second lower clamp; an impedance tester, electrically connected to the first upper clamp, the first lower clamp, the second upper clamp and the second lower clamp; and a processor, electrically connected to the impedance tester, wherein the first upper clamp and the second upper clamp are configured to simultaneously move along a longitudinal direction. The present invention further discloses a method for measuring interfacial contact impedance which may utilize the first fixture and the second fixture to simultaneously measure impedances of at least two samples. Thereby, the present invention can provide an advantageous technique for quickly and precisely measuring surface contact impedances of samples.

Description

Impedance measuring device and method of measuring surface contact impedance

The present invention relates to an impedance measuring device and method, and in particular to a measuring device and method capable of quickly and accurately measuring surface contact impedance.

The internal impedance of a fuel cell is an important indicator for evaluating the performance of a cell and is also a key parameter for the efficiency of a fuel cell stack. Therefore, the technology for accurately measuring the internal impedance of a fuel cell is extremely important for the development of fuel cells.

Generally speaking, a fuel cell assembly is composed of several layers of sheets, such as the electrode or the gas diffusion layer. Since the contact surface between the sheets is microscopically uneven, there is a significant surface contact impedance on the contact surface, especially the contact surface between the electrode and the gas diffusion layer. Therefore, even a slight change in the surface contact impedance will have a huge impact on the power of the fuel cell stack. In other words, the laminate composed of several layers of sheets inside the fuel cell has a great impact on the internal impedance of the fuel cell.

As shown in Figure 1, it is a schematic diagram of the measurement principle of surface contact impedance. In the conventional technology, the surface contact resistance value between the gas diffusion layer and the electrode plate can be obtained through a two-stage measurement technology. Specifically, a sample is first provided, and the sample is a laminate composed of the gas diffusion layer 203 , the electrode plate 204 , and the gas diffusion layer 203 . Next, the ohmic impedance Rs ₁ of the sample is measured. Further, the electrode plate 204 is taken out from the sample to form a laminate composed of two gas diffusion layers 203 . Then, the ohmic impedance Rs ₂ of the sample is measured. Finally, the ohmic impedance values obtained from the two measurements are subtracted and divided by 2 to obtain the surface contact impedance value between the gas diffusion layer and the electrode plate. In other words, the surface contact resistance value between the gas diffusion layer 203 and the electrode plate 204 can be expressed by the following formula: surface contact resistance = (Rs ₁ −Rs ₂ )/2.

However, due to the design of the conventional impedance measurement device, at least two measurements are required before the surface contact impedance can be measured. Therefore, the existing surface contact impedance measurement technology consumes a lot of time. In addition, the operation of removing the electrode plate from the sample can easily destroy the microscopic appearance of the gas diffusion layer surface, reducing the accuracy of the measurement results. Therefore, there is an urgent need for an impedance measuring device that can simplify the process of measuring surface contact impedance, quickly measure surface contact impedance, and can also improve the accuracy of surface contact impedance measurement results.

In order to solve the above technical problems, the present invention provides an impedance measuring device, which includes: a first fixture, including a first upper clamp and a first lower clamp; a second fixture, including a second upper clamp and a second lower clamp; an impedance tester, electrically connected to the first upper clamp, the first lower clamp, the second upper clamp, and the second lower clamp; and a processor, electrically connected to the impedance tester; wherein the first upper clamp and the second upper clamp are configured to move longitudinally synchronously; wherein, during measurement, the first lower clamp carries a first sample, and the second lower clamp carries a second sample, wherein the impedance tester is configured to measure a first impedance value of the first sample, and a second impedance value of the second sample, and the processor is configured to calculate a third impedance value based on the first impedance value and the second impedance value. By using the first upper clamp and the second upper clamp to move longitudinally synchronously, the present invention can simplify the measurement process, thereby quickly measuring multiple impedance values.

The impedance measurement device provided by the present invention may further include a lifting platform and a carrier platform parallel to the lifting platform, wherein the first upper clamp part and the second upper clamp part are arranged on the lifting platform, and the first lower clamp part and The second lower clamp is disposed on the carrier.

The impedance measuring device provided by the present invention may further include a press connected to the lifting platform, and the press is configured to drive the longitudinal movement of the lifting platform. In a specific embodiment, the impedance measurement device provided by the present invention may include: a press; a lifting platform connected to the press; a carrier platform parallel to the lifting platform; a first fixture including a first upper clamp part and The first lower clamp part, the first upper clamp part is arranged on the lifting platform, the first lower clamp part is arranged on the carrier platform; the second fixture includes a second upper clamp part and a second lower clamp part, The second upper clamp part is arranged on the lifting platform, and the second lower clamp part is arranged on the stage; the impedance tester is electrically connected to the first upper clamp part, the first lower clamp part, and the third The two upper clamp parts, the second lower clamp part, and the processor are electrically connected to the press machine and the impedance tester.

The first lower clamp part and the second lower clamp part in the impedance measuring device provided by the present invention are used to carry the sample to be measured. In a specific embodiment, the first lower clamp portion carries the first sample, the second lower clamp portion carries the second sample, the impedance tester is configured to measure the first impedance value of the first sample, and The second impedance value of the second sample.

The impedance tester in the impedance measuring device provided by the present invention may include at least one impedance sensing element, and the at least one impedance sensing element is used to detect the impedance of the sample. The arrangement of the at least one impedance sensing element is not limited, and the impedance sensing element can be arranged on the first fixture and the second fixture in a fixed manner or a detachable manner. In a specific embodiment, the at least one impedance sensing element is detachably arranged on the first fixture and the second fixture. In another specific embodiment, the at least one impedance sensing element is fixedly arranged on the first fixture and the second fixture.

The processor in the impedance measurement device provided by the present invention can be configured to calculate a third impedance value based on the first impedance value and the second impedance value. In a specific embodiment, the first sample includes a laminate having a gas diffusion layer, a plate, and a gas diffusion layer stacked in sequence, and the second sample includes a laminate having two gas diffusion layers stacked on each other, and the third impedance value is half of the difference between the first impedance value and the second impedance value.

The press in the impedance measuring device provided by the present invention includes a servo motor and an electric cylinder. The servo motor is coupled to the electric cylinder. The electric cylinder is connected to the lifting platform. The servo motor is configured to control the longitudinal movement of the electric cylinder. , to drive the ascending stroke of the lifting platform or the descending stroke of the lifting platform. The coupling method of the servo motor and the electric cylinder is not limited, and the servo motor can be electrically connected to or perpendicular to the electric cylinder. In a specific embodiment, the servo motor is perpendicular to the electric cylinder, and the servo motor is electrically connected to the electric cylinder.

The impedance measuring device provided by the present invention may further include a temperature regulator electrically connected to the first upper clamp part, the first lower clamp part, the second upper clamp part and the second lower clamp part, Wherein the thermostat is configured to adjust the temperature of at least one of the first upper clamp part, the first lower clamp part, the second upper clamp part and the second lower clamp part to increase or decrease the first The temperature of at least one of the upper clamp part, the first lower clamp part, the second upper clamp part and the second lower clamp part. In some embodiments, the thermostat may include a heater configured to heat the first upper clamp, the first lower clamp, the second upper clamp, and the second lower clamp. At least one. In some embodiments, the thermostat may include at least one temperature sensing element configured to detect the first upper clamp portion, the first lower clamp portion, the second upper clamp portion The temperature of at least one of the lower clamp portion and the second lower clamp portion. In addition, the arrangement manner of the at least one temperature sensing element is not limited. The temperature sensing element can be fixedly or detachably arranged on the first fixture and the second fixture. In a specific embodiment, the at least one temperature sensing element is detachably disposed on the first fixture and the second fixture. In another specific embodiment, the at least one temperature sensing element is fixedly disposed on the first fixture and the second fixture.

The impedance measurement device provided by the present invention may further include a user interface that communicates with the processor. In some embodiments, the user interface can communicate with the processor via wired communication. For example, the user interface can communicate with the processor via an Ethernet cable, a USB cable, or an RJ6 cable. In some embodiments, the user interface can communicate with the processor wirelessly. For example, the user interface can communicate with the processor through Wi-Fi (802.11 standard), Bluetooth, cellular communication or near field wireless communication device. wireless communication.

The user interface in the impedance measurement device provided by the present invention can be a screen, a touch screen, a smart device, a computer or any human-machine interface device. In a specific embodiment, the user can input a setting value of at least one of the pressing pressure, temperature and measurement time through the user interface, so that the processor communicating with the user interface controls the press, the impedance tester, or the thermostat according to the input setting value.

The carrier in the impedance measuring device provided by the present invention may further include a turntable, wherein the first lower clamp and the second lower clamp are arranged on the turntable. In a specific embodiment, when the turntable is in a first measuring position, the first upper clamp is coupled to the first lower clamp, and the second upper clamp is coupled to the second lower clamp. In a specific embodiment, when the turntable is in a second measuring position, the first upper clamp is coupled to the second lower clamp, and the second upper clamp is coupled to the first lower clamp. In a specific embodiment, when the turntable is in a first measuring position, the first upper clamp is aligned with the first lower clamp, and the second upper clamp is coupled to the second lower clamp. In a specific embodiment, when the turntable is in the second measuring position, the first upper clamp is aligned with the second lower clamp, and the second upper clamp is coupled to the first lower clamp.

The processor in the impedance measuring device provided by the present invention can be electrically connected to at least one of a press, an impedance tester, a temperature regulator, a user interface and a turntable.

The processor in the impedance measurement device provided by the present invention can communicate with at least one of a press, an impedance tester, a temperature regulator, a user interface and a turntable via wired or wireless communication to exchange data. In some embodiments, the processor may be in wired communication with at least one of the press, the impedance tester, the thermostat, the user interface, and the turntable via an Ethernet cable, a USB cable, or an RJ6 cable. In some embodiments, the processor can communicate with at least one of the press, the impedance tester, the thermostat, the user interface, and the turntable via Wi-Fi (802.11 standard), Bluetooth, cellular communications, or near field The wireless communication device performs wireless communication with the processor.

Another object of the present invention is to provide a method for measuring contact impedance, which includes the steps of: (a) providing the above-mentioned impedance measuring device; (b) performing a calibration operation on the impedance measuring device; (c) applying the first sample to and the second sample are respectively placed on the first lower clamp part and the second lower clamp part, wherein the first sample includes a laminate having a gas diffusion layer, an electrode plate, and a gas diffusion layer stacked in sequence, and the The second sample includes a laminate with two gas diffusion layers stacked on each other; (d) sandwiching the first sample and the second sample between the first upper clamp part and the first lower clamp part respectively , and between the second upper clamp part and the second lower clamp part to apply pressing pressure on the first sample and the second sample; (e) By using an impedance tester, measure the first the first impedance value of the sample, and the second impedance value of the second sample; and (f) obtaining the surface contact impedance value between the gas diffusion layer and the electrode plate through calculation by the processor, wherein the The surface contact resistance value is half of the difference between the first resistance value and the second resistance value.

The step (b) of the method for measuring contact impedance provided by the present invention comprises the steps of: (b-1) placing a standard sample in the first lower clamp; (b-2) clamping the standard sample between the first upper clamp and the first lower clamp; (b-3) measuring a first calibration value of the standard sample by using an impedance tester; (b-4) placing the standard sample in the second lower clamp; (b-5) clamping the standard sample between the second upper clamp and the second lower clamp; (b-6) measuring a second calibration value of the standard sample by using an impedance tester; (b-7) The processor calculates a calibration error, wherein the calibration error is the absolute value of the difference between the first calibration value and the second calibration value divided by the first calibration value; and (b-8) if the calibration error is greater than a predetermined value, the setting parameters of the impedance measurement device are adjusted, and steps (b-1) to (b-7) are repeated; if the calibration error is not greater than the predetermined value, the calibration operation of the impedance measurement device is terminated. In some specific embodiments, the predetermined value is 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10%.

The method for measuring contact impedance provided by the present invention further comprises the steps of: (g) adjusting the descending stroke of the lifting platform to change the pressing pressure applied to the first sample and the second sample; and (h) repeating steps (e) to (f) in the above method of the present invention. In some specific embodiments, steps (g) and (h) in the method for measuring contact impedance provided by the present invention can be repeated multiple times to measure the surface contact impedance values under multiple pressures, so that the present invention can provide a relationship chart between the surface contact impedance of the sample and the pressure.

The method for measuring contact impedance provided by the present invention further includes the steps of: (i) adjusting the turntable from the first measurement position to the second measurement position, wherein when the turntable is in the first measurement position, the first upper clamp portion is coupled to the The first lower clamp part, the second upper clamp part couples with the second lower clamp part, when the turntable is in the second measurement position, the first upper clamp part couples with the second lower clamp part, the second upper clamp part Couple the first lower clamp part; (j) Repeat steps (e) to (f) in the method of the present invention to obtain the reference surface contact resistance value between the gas diffusion layer and the electrode plate; and (k) The processor calculates the average value of the surface contact resistance value and the reference surface contact resistance value to obtain an optimized surface contact resistance value.

The present invention can simultaneously measure the impedance of at least two samples to calculate the surface contact impedance of the target object to be measured by at least the technical features of "a first jig and a second jig", thereby avoiding the repeated removal and placement of samples from the jig, thereby simplifying the measurement process and saving measurement time. On the other hand, since the repeated removal and placement of samples from the jig can be avoided, the surface state of the sample and the surface state of the jig can be prevented from being damaged, thereby obtaining more accurate measurement results. In addition, the present invention can alternately use the impedance sensing elements of the two sets of jigs to quickly obtain multiple sets of measurement results while avoiding the repeated removal and placement of samples from the jig by at least the technical features of "a combination of a first jig, a second jig and a turntable", thereby calculating and obtaining optimized surface contact impedance values to provide more accurate measurement results.

2 to 4, which show schematic diagrams of an embodiment of an impedance measurement device 100 according to the present invention.

In this embodiment, the impedance measuring device 100 may include a press 101, a lifting platform 102, a carrier 103, a first fixture 104, a second fixture 105, an impedance tester 106, a processor 107, a temperature regulator 109, and a user interface 108. As shown in FIG3 , the press 101 may include a servo motor 1011 and an electric cylinder 1012, wherein the servo motor 1011 is coupled to the electric cylinder 1012, and the electric cylinder 1012 is connected to the lifting platform 102. The carrier 103 is configured to be parallel to the lifting platform 102. The first fixture 104 includes a first upper clamp 1041 and a first lower clamp 1042, wherein the first upper clamp 1041 is configured on the lifting platform 102, and the first lower clamp 1042 is configured on the carrier 103. The second fixture 105 includes a second upper clamp 1051 and a second lower clamp 1052. The second upper clamp 1051 is disposed on the lifting platform 102, and the second lower clamp 1052 is disposed on the carrier 103. The impedance tester 106 is electrically connected to the first upper clamp 1041, the first lower clamp 1042, the second upper clamp 1051, and the second lower clamp 1052. As shown in FIG. 4 , the processor 107 can be electrically connected to the press 101, the impedance tester 106, the temperature regulator 109, and the user interface 108.

5 to 6, which show a flow chart of an embodiment of a method for measuring contact impedance according to the present invention.

As shown in Figure 5, the method of measuring contact impedance in this embodiment includes the steps: (S1) Provide the impedance measurement device 100 as shown in Figure 2; (S2) Perform a calibration operation on the impedance measurement device 100; (S3) As As shown in Figure 2, two sets of impedance sensing elements, the first sample 201 and the second sample 202 are placed on the first lower clamp part 1042 and the second lower clamp part 1052 respectively, where the first sample 201 includes a A laminate of stacked gas diffusion layers 203, electrode plates 204, and gas diffusion layers 203. The second sample 202 includes a laminate having two layers of gas diffusion layers 203 stacked on each other; (S4) driven by using the press 101 The descending stroke of the lifting platform 102 clamps the first sample 201 and the second sample 202 between the first upper clamp part 1041 and the first lower clamp part 1042, and the second upper clamp part 1051 and the second lower clamp respectively. 1052 to apply pressing pressure on the impedance sensing element, the first sample 201 and the second sample 202; (S5) By using the impedance tester 106, measure the first impedance value of the first sample 201 , and the second impedance value of the second sample 202; and (S6) through calculation by the processor 107, obtain the surface contact impedance value between the gas diffusion layer 203 and the electrode plate 204, where the surface contact impedance value is the first impedance. half the difference between the value and the second impedance value. In other words, the surface contact resistance value between the gas diffusion layer 203 and the electrode plate 204 can be expressed by the following formula, where Rs ₁ is the first resistance value and Rs ₂ is the second resistance value: Surface contact resistance = (Rs ₁ −Rs ₂ ) /2.

On the other hand, as shown in FIG. 6 , the calibration operation of step (S2) includes the steps: (S2-1) placing the standard sample on the first lower clamp 1042; (S2-2) driving by using the press 101 The descending stroke of the lifting platform 102 clamps the standard sample between the first upper clamp part 1041 and the first lower clamp part 1042; (S2-3) By using the impedance tester 106, the first calibration of the standard sample is measured value; (S2-4) Place the standard sample in the second lower clamp part 1052; (S2-5) By using the press 101 to drive the downward stroke of the lifting platform 102, clamp the standard sample in the second upper clamp part 1051 and the second lower clamp part 1052; (S2-6) By using the impedance tester 106, the second calibration value of the standard sample is measured; (S2-7) Through the calculation of the processor 107, the calibration error is obtained , where the calibration error is the absolute value of the difference between the first calibration value and the second calibration value divided by the first calibration value; and (S2-8) if the calibration error is greater than 3%, adjust the setting parameters of the impedance measurement device 100 and repeat the steps (S2-1) to (S2-7); if the calibration error is not greater than 3%, end the calibration operation of the impedance measuring device 100. Furthermore, through the calibration operation of this embodiment, errors between successive measurement results can be reduced. Therefore, the present invention is beneficial to providing more accurate surface contact impedance measurement values.

Refer to Figure 7, which shows a flow chart of another embodiment of the method for measuring contact impedance according to the present invention.

The content of this embodiment is substantially the same as that of the previous embodiment. The method for measuring contact impedance of this embodiment further includes the steps of: (S7) adjusting the descending stroke of the lifting platform 102 to change the pressing pressure applied to the impedance sensing element, the first sample 201 and the second sample 202; and (S8) repeating steps (S5) to (S6). By the method provided in this embodiment, the pressing pressure applied to the first sample 201 and the second sample 202 can be adjusted several times, and the surface contact impedance under various pressing pressures can be measured. Specifically, the pressing pressure applied to the first sample 201 and the second sample 202 can be gradually increased or decreased, and finally the correlation data of the pressing pressure and the surface contact impedance can be obtained.

In other embodiments, the surface contact impedance measured under various pressing pressures can be stored in the memory unit of the processor 107, and the processor 107 analyzes the accumulated measurement data and transmits the analysis results to the user interface 108, which presents the analysis results in a graphical form, so that the user can obtain a relationship diagram between the pressing pressure and the surface contact impedance.

8 to 9, which show schematic diagrams of an embodiment of an impedance measurement device 100 according to the present invention.

In this embodiment, the impedance measurement device 100 may include a press 101, a lifting platform 102, a carrier 103, a first jig 104, a second jig 105, an impedance tester 106, a processor 107, a temperature regulator 109 and a user. user interface 108, in which the stage 103 includes a turntable 110. The press 101 may include a servo motor 1011 and an electric cylinder 1012. The servo motor 1011 is coupled to the electric cylinder 1012, and the electric cylinder 1012 is connected to the lifting platform 102. The stage 103 is arranged parallel to the lifting platform 102 . The first fixture 104 includes a first upper clamp part 1041 and a first lower clamp part 1042. The first upper clamp part 1041 is arranged on the lifting platform 102, and the first lower clamp part 1042 is arranged on the turntable 110. The second fixture 105 includes a second upper clamp part 1051 and a second lower clamp part 1052. The second upper clamp part 1051 is arranged on the lifting platform 102, and the second lower clamp part 1052 is arranged on the turntable 110. Furthermore, when the turntable 110 is in the first measurement position, the first upper clamp part 1041 is coupled to the first lower clamp part 1042, and the second upper clamp part 1051 is coupled to the second lower clamp part 1052. When the turntable 110 is in the second measurement position, , the first upper clip portion 1041 is coupled to the second lower clip portion 1052, and the second upper clip portion 1051 is coupled to the first lower clip portion 1042. In addition, the impedance tester 106 is electrically connected to the first upper clamp part 1041, the first lower clamp part 1042, the second upper clamp part 1051, and the second lower clamp part 1052. As shown in FIG. 9 , the processor 107 can be electrically connected to the press 103 , the impedance tester 106 , the thermostat 109 , the user interface 108 and the turntable 110 .

Referring to Figure 10, a flow chart of one embodiment of a method for measuring contact impedance according to the present invention is shown.

As shown in Figure 10, the method of measuring contact impedance in this embodiment includes the steps: (S1) Provide the impedance measurement device 100 as shown in Figure 2; (S2) Perform a calibration operation on the impedance measurement device 100; (S3) As As shown in Figure 11, two sets of impedance sensing elements, the first sample 201 and the second sample 202 are placed on the first lower clamp part 1042 and the second lower clamp part 1052 respectively, where the first sample 201 includes a A laminate of stacked gas diffusion layers 203, electrode plates 204, and gas diffusion layers 203. The second sample 202 includes a laminate having two layers of gas diffusion layers 203 stacked on each other; (S4) driven by using the press 101 The descending stroke of the lifting platform 102 clamps the first sample 201 and the second sample 202 between the first upper clamp part 1041 and the first lower clamp part 1042, and the second upper clamp part 1051 and the second lower clamp respectively. between the parts 1052 to apply pressing pressure to the first sample 201 and the second sample 202; (S5) By using the impedance tester 106, measure the first impedance value of the first sample 201 and the second sample The second impedance value of 202; (S6) Through calculation by the processor 107, the surface contact impedance value between the gas diffusion layer 203 and the electrode plate 204 is obtained, where the surface contact impedance value is the first impedance value and the second impedance value. half of the difference; (S7') Adjust the turntable 110 from the first measurement position to the second measurement position; (S8') Repeat steps (S5) to (S6) to obtain the gap between the gas diffusion layer 203 and the electrode plate 204 The reference surface contact impedance value; and (S9') the processor 107 calculates the surface contact impedance value and the average value of the reference surface contact impedance value to obtain an optimized surface contact impedance value. In other words, the optimized surface contact impedance value is half of the sum of the surface contact impedance value obtained in step (S6) and the reference surface contact impedance value obtained in step (S9').

Furthermore, during steps (S1) to (S6), the turntable 110 is set to be in the first measurement position. As shown in FIG. 11 , when the turntable 110 is in the first measurement position, the first upper clamp part 1041 is coupled to the first lower clamp part 1042 , and the second upper clamp part 1051 is coupled to the second lower clamp part 1052 . In step (S7'), the turntable 110 is switched from the first measurement position to the second measurement position. As shown in FIG. 12 , when the turntable 110 is in the second measurement position, the first upper clamp part 1041 is coupled to the second lower clamp part 1052 , and the second upper clamp part 1051 is coupled to the first lower clamp part 1042 . By switching the turntable 110 between the first measurement position and the second measurement position, the impedance sensing element, the first sample 201 and the second sample 202 can be quickly used interchangeably, which is conducive to faster and more efficient design. Diversified and more accurate measurement technology also helps to quickly detect excessive errors in the measurement results of the two sets of fixtures, so that the measurement device can be recalibrated.

Furthermore, the method of the present invention facilitates the alternate use of different impedance sensing elements without the need to repeatedly remove the sample from the fixture and then insert it, thus simplifying the measurement process. Not only that, it can also quickly obtain the reference surface contact impedance value without damaging the surface of the sample, thereby improving the accuracy of the measured surface contact impedance.

100: Impedance measuring device 101:Press 1011:Servo motor 1012: Electric cylinder 102: Lifting platform 103: Carrier platform 104:The first fixture 1041: First upper clamping part 1042: First lower clamping part 105: Second fixture 1051: The second upper clamp part 1052: The second lower clamp part 106:Impedance tester 107: Processor 108:User interface 109: Thermostat 110:Turntable 201:First sample 202:Second sample 203: Gas diffusion layer 204:Plate S1: Steps S2: Step S3: Steps S4: Steps S5: Steps S6: Steps S7: Steps S8: Steps S9: Steps S2-1: Steps S2-2: Steps S2-3: Steps S2-4: Steps S2-5: Steps S2-6: Steps S2-7: Steps S2-8: Steps

FIG1 is a schematic diagram showing the measurement principle of surface contact impedance; FIG2 is a schematic diagram showing an impedance measuring device 100 according to an embodiment of the present invention; FIG3 is a schematic diagram showing an impedance measuring device 100 according to an embodiment of the present invention; FIG4 is a schematic diagram showing an impedance measuring device according to an embodiment of the present invention; FIG5 is a flow chart showing a method for measuring contact impedance according to an embodiment of the present invention; FIG6 is a flow chart showing a method for measuring contact impedance according to an embodiment of the present invention; FIG7 is a flow chart showing a method for measuring contact impedance according to an embodiment of the present invention; FIG8 is a schematic diagram showing an impedance measuring device 100 according to an embodiment of the present invention; FIG9 is a schematic diagram showing an impedance measuring device according to an embodiment of the present invention; FIG. 10 is a flow chart showing a method for measuring contact impedance according to an embodiment of the present invention; FIG. 11 is a schematic diagram of an impedance measuring device 100 according to an embodiment of the present invention; and FIG. 12 is a schematic diagram of an impedance measuring device 100 according to an embodiment of the present invention.

(without)

100: Impedance measuring device

101: Press machine

1011:Servo motor

1012: Electric cylinder

102: Lifting platform

103: Carrier

104: The first fixture

1041: First upper clamp

1042: First lower clamp

105: Second fixture

1051: Second upper clamp

1052: Second lower clamp

106: Impedance tester

108:User interface

Claims (11)

An impedance measuring device containing: The first fixture includes a first upper clamping part and a first lower clamping part; The second fixture includes a second upper clamp part and a second lower clamp part; An impedance tester, electrically connected to the first upper clamp part, the first lower clamp part, the second upper clamp part, and the second lower clamp part; and A processor, electrically connected to the impedance tester; Wherein the first upper clamp part and the second upper clamp part are arranged to move longitudinally simultaneously; Wherein, during measurement, the first lower clamp part carries the first sample, and the second lower clamp part carries the second sample, The impedance tester is configured to measure the first impedance value of the first sample and the second impedance value of the second sample, and the processor is configured to calculate based on the first impedance value and the second impedance value. The third impedance value. The device according to claim 1 further includes a lifting platform and a carrier platform parallel to the lifting platform, wherein the first upper clamp part and the second upper clamp part are arranged on the lifting platform, and the first lower clamp part And the second lower clamp is arranged on the carrier platform. The device as claimed in claim 1 further includes a press connected to the lifting platform, and the press is configured to drive the longitudinal movement of the lifting platform. The device as described in claim 3, wherein the press comprises a servo motor and an electric cylinder, the servo motor is coupled to the electric cylinder, the electric cylinder is connected to the lifting platform, wherein the servo motor is configured to control the longitudinal movement of the electric cylinder to drive the lifting platform to move upward or downward. The device according to claim 1, further comprising a thermostat electrically connected to the first upper clamp part, the first lower clamp part, the second upper clamp part and the second lower clamp part , The thermostat is configured to adjust the temperatures of the first upper clamp part, the first lower clamp part, the second upper clamp part and the second lower clamp part. The device as described in claim 1 further includes a user interface that communicates with the processor. The device as described in claim 1, wherein the carrier further comprises a turntable, the first lower clamp and the second lower clamp are arranged on the turntable, when the turntable is in a first measuring position, the first upper clamp is coupled to the first lower clamp, and the second upper clamp is coupled to the second lower clamp, when the turntable is in a second measuring position, the first upper clamp is coupled to the second lower clamp, and the second upper clamp is coupled to the first lower clamp. A method of measuring contact impedance, including steps: (a) Provide an impedance measuring device as described in any one of claims 1 to 7; (b) Perform calibration operations on the impedance measuring device; (c) Place the first sample and the second sample on the first lower clamp part and the second lower clamp part respectively, wherein the first sample includes a gas diffusion layer, an electrode plate, and a gas diffusion layer stacked in sequence. A laminate of gas diffusion layers, the second sample comprising a laminate of two gas diffusion layers stacked on each other; (d) Sandwich the first sample and the second sample respectively between the first upper clamp part and the first lower clamp part, and between the second upper clamp part and the second lower clamp part , to apply pressing pressure to the first sample and the second sample; (e) By using the impedance tester, measure the first impedance value of the first sample and the second impedance value of the second sample; and (f) Obtain the surface contact resistance value between the gas diffusion layer and the electrode plate through calculation by the processor, wherein the surface contact resistance value is the difference between the first resistance value and the second resistance value half. The method as described in request item 8, wherein step (b) includes the following steps: (b-1) Place the standard sample on the first lower clamp; (b-2) Clamp the standard sample between the first upper clamp part and the first lower clamp part; (b-3) By using the impedance tester, measure the first calibration value of the standard sample; (b-4) Place the standard sample on the second lower clamp; (b-5) Clamp the standard sample between the second upper clamp part and the second lower clamp part; (b-6) By using the impedance tester, measure the second calibration value of the standard sample; (b-7) Obtain a calibration error through calculation by the processor, wherein the calibration error is the absolute value of the difference between the first calibration value and the second calibration value divided by the first calibration value; and (b-8) If the calibration error is greater than the predetermined value, adjust the setting parameters of the impedance measuring device and repeat steps (b-1) to (b-7); if the calibration error is not greater than the predetermined value, end the Calibration operations for impedance measuring devices. The method as described in claim 8 further comprises the steps of: (g) changing the pressing pressure applied to the first sample and the second sample; and (h) repeating steps (e) to (f). The method as described in claim 8, wherein the carrier further comprises a turntable, the first lower clamp and the second lower clamp are arranged on the turntable, and the method for measuring contact impedance further comprises the following steps: (i) adjusting the turntable from a first measurement position to a second measurement position, wherein when the turntable is at the first measurement position, the first upper clamp is coupled to the first lower clamp, and the second upper clamp is coupled to the second lower clamp, and when the turntable is at the second measurement position, the first upper clamp is coupled to the second lower clamp, and the second upper clamp is coupled to the first lower clamp; (j) repeating steps (e) to (f) to obtain a reference surface contact impedance value between the gas diffusion layer and the electrode; and (k) The processor calculates the average value of the surface contact impedance value and the reference surface contact impedance value to obtain an optimized surface contact impedance value.

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