CN110988480A - Device and method for measuring conductivity of proton exchange membrane in thickness direction - Google Patents
Device and method for measuring conductivity of proton exchange membrane in thickness direction Download PDFInfo
- Publication number
- CN110988480A CN110988480A CN201910994068.9A CN201910994068A CN110988480A CN 110988480 A CN110988480 A CN 110988480A CN 201910994068 A CN201910994068 A CN 201910994068A CN 110988480 A CN110988480 A CN 110988480A
- Authority
- CN
- China
- Prior art keywords
- electrode
- lead
- proton exchange
- exchange membrane
- membrane
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/041—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
Landscapes
- Chemical & Material Sciences (AREA)
- General Physics & Mathematics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- Electrochemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Molecular Biology (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
- Fuel Cell (AREA)
Abstract
The invention provides a device and a method for measuring conductivity of a proton exchange membrane in a membrane thickness direction, belonging to the technical field of fuel cell testing devices. The invention is provided with the weight table, the contact condition of the membrane and the electrodes at two ends of the membrane can be accurately controlled by adjusting the weight, the contact resistance error of the electrodes and the membrane during multiple measurements is reduced, and the relative test precision is ensured.
Description
Technical Field
The invention belongs to the technical field of fuel cell testing devices, and particularly relates to a device and a method for measuring conductivity of a proton exchange membrane in the membrane thickness direction.
Background
In the measurement of the conductivity of the proton exchange membrane of the fuel cell in the thickness direction, a linearly changing direct current voltage is applied to the membrane, the current passing through the proton exchange membrane is measured, and the conductivity of the membrane is calculated by ohm's law. The phenomenon of double layer polarization of the electrode and the film has a large effect on the resistance of the film in a direct current test, and the problem of polarization is complex, not only related to the applied direct current voltage, but also related to the electrode material, shape and flatness. That is, for a solid electrolyte such as a proton exchange membrane, if an electric field voltage is applied, the internal protons H + will move to the cathode to form a current in the proton exchange membrane, but at the same time, the anions in the proton exchange membrane, such as SO32 ", are fixed on the polymer chains of the proton exchange membrane and cannot move, and at the same time, no protons are supplemented, SO that a reverse potential, i.e., a polarization potential, is formed inside the proton exchange membrane, which will cause the ammeter to decay rapidly. Therefore, the measurement of the resistivity of the proton exchange membrane in the membrane thickness direction is difficult, the conductivity of the membrane is difficult to measure under certain precision through the traditional ohm's law, the preparation method of the sample to be measured is complicated, and the batch verification of the conductivity of the proton conduction membrane of the fuel cell in the membrane thickness direction is difficult to realize in the production process.
Disclosure of Invention
In order to solve the existing problems, the invention provides a device and a method for measuring the conductivity of a proton exchange membrane in the membrane thickness direction.
In order to solve the technical problems, the invention provides a device for measuring the conductivity of a proton exchange membrane in the thickness direction, which comprises an insulating base, wherein a supporting frame is arranged on the insulating base, a baffle is arranged above the supporting frame, a linear bearing is arranged in the center of the baffle, a needle-shaped electrode shaft moves under the restraint of the linear bearing and is perpendicular to the insulating base, a weight table is arranged at the top end above the needle-shaped electrode baffle, a conical electrode is arranged at the bottom below the needle-shaped electrode baffle, a transparent plate is arranged on the insulating base below the conical electrode, a cylindrical electrode is arranged on the insulating base below the transparent plate, a proton conducting membrane is laid between the cylindrical electrode and the transparent plate, and the conical electrode can vertically move up and down above the transparent plate to fasten the proton conducting membrane.
As a preferable scheme, the conical electrode comprises a conical body, a circular pore channel with the diameter of 0.8-1 mm is arranged in the conical body, and a lead I is fixedly penetrated in the circular pore channel along the direction of a central line to form the electrode;
the conical electrode and the needle electrode shaft move perpendicular to the insulating base under the restraint of the linear bearing, the distance from the surface of the cylindrical electrode is 100mm when the needle electrode shaft moves to the highest point, and the conical electrode, the proton exchange membrane and the cylindrical electrode are clamped to form an electrochemical system electrode when the needle electrode shaft moves to the lowest point.
As a preferable scheme, the cylindrical electrode comprises a groove arranged on the insulating base, and the groove is in a cylindrical shape with the depth of 2mm and the diameter of 2 mm; and a lead II and an electrode end thereof are embedded in the groove, the center of the electrode end face of the lead II is vertically aligned with the electrode end face of the lead I after the installation is finished, and the other ends of the lead I and the lead II are connected with an electrochemical workstation.
As a preferable scheme, the transparent pressing plate is in a cuboid shape, a conical groove is formed in the center of the transparent pressing plate, vertical ventilating through holes are formed in a conical inclined plane of the conical groove, the diameter of each through hole is smaller than 2mm, and the number of the through holes is smaller than 30; the conical inclined plane of the pressure transmission plate is consistent with the conical taper of the conical body.
As a preferable scheme, positioning holes are formed in the edges of the periphery of the transparent pressing plate, holes corresponding to the positioning holes are formed in the insulating base, and the diameter of each hole is larger than the diameter of each fastening bolt by 1 mm; the relative position deviation between the positioning hole and the opening hole on the insulating base is not more than 1 mm.
As a preferred scheme, locating slots are arranged on two sides of the transparent pressing plate, locating blocks corresponding to the locating slots are arranged on the insulating base, and the transparent pressing plate and the insulating base are fixed through fastening bolts.
The device for measuring the conductivity of the proton exchange membrane in the membrane thickness direction according to claim 1, wherein the needle electrode shaft, the cylindrical electrode, the permeable plate and the insulating base are made of non-conductive material such as polyetheretherketone, polytetrafluoroethylene or PET polymer;
the lead I and the lead II are made of platinum, gold-plated copper and silver with low resistivity;
the volume resistivity of the non-conductive material is 900-1100 omega cm.
The method for measuring the conductivity of the proton exchange membrane in the membrane thickness direction comprises the following steps:
A. selecting electrodes and leads I, II and proton exchange membrane sample sheets which meet the standard;
B. and lifting the weight table up axially through the needle electrode, loosening the fastening screw of the transparent pressing plate and the insulating base, and taking down the transparent pressing plate.
C. Spreading the proton exchange membrane to be tested on an insulating base to completely cover the electrode of a lead II on the insulating base, flatly pressing a transparent pressing plate with a ventilation through hole on the proton exchange membrane to be tested, and slowly dropping a needle-shaped electrode shaft lined with the lead I to lightly press the needle-shaped electrode shaft on the thin film to be tested;
D. and a weight is placed on a weight table on the needle-shaped electrode shaft, the mass of the weight pressurizes the needle-shaped electrode shaft, and the electrode end plane of the lead I, the electrode end plane of the lead II and the proton exchange membrane to be tested between the electrode end plane of the lead I and the electrode end plane of the lead II are stacked together, so that the proton exchange membrane to be tested has no folds.
E. Placing the testing device with the proton exchange membrane installed in a constant temperature and humidity box, clamping a lead I and a lead II by using metal clamps in the constant temperature and humidity box respectively, and then connecting electrodes of an electrochemical workstation with a power supply wire outside the constant temperature and humidity box; and starting an alternating current impedance test program, measuring and reading an impedance value, and calculating the conductivity.
As a preferred scheme, the step a specifically includes the following steps: a, measuring the areas S1 and S2 of the electrode terminal of the lead wire I and the electrode terminal of the lead wire II, so that S1-S2 is less than 0.005S 1;
b, placing the electrode end of the lead I and the electrode end of the lead II in a 5% dilute nitric acid solution for soaking for 24 hours to remove organic stains or impurity metal particles on the surfaces of the electrodes;
c, setting the parameters of the constant temperature and humidity box into environmental conditions of temperature and humidity, and standing for 2 hours;
d, selecting a proton exchange membrane to be tested, cutting the proton exchange membrane into sample pieces, wherein the sample pieces are smaller than a transparent pressing plate on the device, and the length and the width of each sample piece are respectively smaller than 5mm of the length and the width of the transparent pressing plate, so that the proton exchange membrane is ensured not to be damaged by fixing screws of the insulating base.
As a preferable scheme, the step E specifically comprises the steps of measuring an impedance map of the proton exchange membrane applied between the conical electrode and the cylindrical electrode in the frequency range of 1-10MHz and the small-amplitude sine wave perturbation potential amplitude of 100mV through an electrochemical workstation, calculating the conductivity of the proton exchange membrane of the fuel cell membrane in the membrane thickness direction according to an equivalent circuit and a conductivity formula, changing the contact pressure of the conical electrode by adjusting the weight and the number of the weights on the weight plate, reducing the influence of the contact resistance on the measurement result, polishing the electrode end of the lead I and the electrode end of the wire II on a polishing cloth by using α -Al2O3 with the diameter of 0.05 mu m, and carrying out ultrasonic treatment on the electrode end and the electrode end of the wire II in acetone and water for 10-100min in sequence so as to ensure the contact state of the electrode and the membrane to be.
The invention has the beneficial effects that:
according to the invention, through the accurate control of the weight, the contact condition of the membrane and the electrodes at two ends of the membrane can be accurately controlled by adjusting the weight, the contact resistance error between the electrodes and the membrane during multiple measurements is reduced, the relative accuracy of the test is ensured, the measurement method is simplified, and the batch verification of the conductivity of the proton conducting membrane of the fuel cell in the membrane thickness direction in the production process is ensured. The device is provided with a weight table.
Drawings
FIG. 1: the invention discloses a schematic diagram of a device for testing the conductivity of a proton conduction membrane in the thickness direction;
FIG. 2: the invention relates to a schematic diagram of a conical electrode of a proton conduction membrane thickness direction conductivity testing device;
FIG. 3: the invention relates to a schematic diagram of a permeable plate of a proton conduction membrane thickness direction conductivity testing device;
FIG. 4: the invention relates to a cylindrical electrode schematic diagram of a proton conduction membrane thickness direction conductivity testing device;
FIG. 5: the invention relates to an equivalent circuit model for proton exchange membrane measurement;
FIG. 6: in embodiment 2 of the present invention, a resistance temperature and humidity characteristic curve;
FIG. 7: embodiment 3 of the present invention is a resistance temperature and humidity characteristic curve;
wherein; 1. a weight table; 2. a needle-shaped electrode shaft; 3. a tapered electrode; 4. a wire I; 5. a pressure-permeable plate; 6. a proton conducting membrane; 7. a wire II; 8. opening a hole; 9. a through hole; 10. positioning a groove; 11. positioning blocks; 12. an insulating base; 13. a pore channel; 14. and (7) positioning the holes.
Detailed Description
In order to make the technical solutions in the present application better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making an innovative effort, shall fall within the scope of protection of the present application.
Example 1:
referring to the attached drawings in the specification, the invention provides a device for measuring the conductivity of a proton exchange membrane in the membrane thickness direction, which comprises an insulating base 12, a supporting frame is arranged on the insulating base 12, a baffle plate is arranged above the supporting frame, a linear bearing is arranged in the center of the baffle plate, the needle-shaped electrode shaft 2 moves perpendicular to the insulating base 12 under the restriction of the linear bearing, a weight table 1 is arranged at the top end of the needle-shaped electrode shaft 2 above the baffle, a conical electrode 3 is arranged at the bottom of the needle-shaped electrode shaft 2 below the baffle, a transparent pressing plate 5 is arranged on an insulating base 12 below the conical electrode 3, a cylindrical electrode is arranged on an insulating base 12 below the pressure transmission plate 5, a proton conducting membrane 6 is laid between the cylindrical electrode and the pressure transmission plate 5, the cone-shaped electrode 3 can vertically move up and down above the transparent pressing plate 5 to fasten the proton conducting membrane 6.
The conical electrode 3 comprises a conical body, a circular hole 13 with the diameter of 0.8-1 mm is formed in the conical body, and a lead I4 penetrates through and is fixed in the circular hole 13 along the central line direction to form an electrode;
the conical electrode 3 and the needle-shaped electrode shaft 2 move perpendicular to the insulating base 12 under the restraint of a linear bearing, the distance from the surface of the cylindrical electrode to the surface of the cylindrical electrode is 100mm when the needle-shaped electrode shaft 2 moves to the highest point, and the conical electrode 3, the proton exchange membrane 6 and the cylindrical electrode are clamped to form an electrochemical system electrode when the needle-shaped electrode shaft 2 moves to the lowest point.
The cylindrical electrode comprises a groove arranged on the insulating base 12, and the groove is cylindrical with the depth of 2mm and the diameter of 2 mm; and a lead II7 and an electrode end thereof are embedded in the groove, the center of the end face of the electrode end of the lead II7 is vertically aligned with the end face of the electrode end of the lead I4 after the installation is finished, and the other ends of the lead I4 and the lead II7 are connected with an electrochemical workstation.
The transparent pressing plate 5 is cuboid in shape, a conical groove is formed in the center of the transparent pressing plate 5, vertical ventilating through holes 9 are formed in the conical inclined plane of the conical groove, the diameter of each through hole 9 is smaller than 2mm, and the number of the through holes 9 is smaller than 30; the conical inclined plane of the transparent pressing plate 5 is consistent with the conical taper of the conical body.
Positioning holes 14 are formed in the peripheral edge of the transparent pressing plate 5, an opening 8 corresponding to the positioning holes 14 is formed in the insulating base 12, and the diameter of the opening 8 is larger than that of the fastening bolt by 1 mm; the relative position deviation between the positioning hole 14 and the opening 8 on the insulating base 12 is not more than 1 mm.
Positioning grooves 10 are formed in two sides of the transparent pressing plate 5, positioning blocks 11 corresponding to the positioning grooves 10 are arranged on the insulating base 12, and the transparent pressing plate 5 and the insulating base 12 are fixed through fastening bolts.
The needle-shaped electrode shaft 2, the cylindrical electrode, the permeable plate 5 and the insulating base 12 are made of non-conductive materials such as polyether-ether-ketone, polytetrafluoroethylene or PET polymer;
the lead I4 and the lead II7 are made of platinum, gold-plated copper and silver with low resistivity;
the volume resistivity of the non-conductive material is 900-1100 omega cm.
Weights with different masses can be placed on the weight table 1, and the contact state of the proton exchange membrane 6 and the electrodes at the two ends of the proton exchange membrane can be accurately controlled by adjusting the mass of the weights; the weight table 1 part is connected with the needle-shaped electrode shaft 2; a lead I4 is placed in the pore passage 13, and one end of the lead I4 is polished to be flat and used as an electrode end and is contacted with the upper surface of the proton exchange membrane 6. The cylindrical electrode of the lead I4 is used as an electrode end, is vertically aligned with the end face of the conical electrode 3, and is contacted and fastened with the upper surface and the lower surface of the proton conducting membrane 6. The other ends of the lead I4 and the lead II7 are connected with an electrochemical workstation;
the proton exchange membrane 6 can be directly communicated with the box body environment of the program-controlled constant temperature and humidity instrument through the through hole 9, and the temperature and humidity environment on the surface of the proton exchange membrane 6 is ensured to be consistent with the outside. The two sides of the transparent pressing plate 5 are provided with positioning grooves 10, so that the positioning is accurate, the connection is reliable, and the function of fixing the film to be detected can be achieved.
The equivalent circuit calculation of the method for providing the proton exchange membrane thickness direction conductivity measuring device adopts a model shown in figure 5: wherein R isΩThe ohmic resistance of the film, or called internal resistance;
Rpthe electrochemical reaction resistance, in this case the sum of the polarization resistance, the interface impedance and the Weber impedance;
CP-double layer capacitance of the membrane to metal platinum interface;
the proton exchange membrane measurement equivalent circuit model complex impedance adopted by the method is as follows:
the real part of the complex model is:
the complex model imaginary part is:
for any one
The values, each having a respective Z' and Z ", are represented in the complex impedance plane as a point connecting each of the values
The impedance point of (2) is a curve obtained in the complex plane, which is called a complex impedance curve.
When in use
When the resistance R of the film is formed, the intersection point of the semicircle and the Z' axisΩ(ii) a When in use
And the intersection point of the semicircle and the Z' axis is Re + Rp. When in use
The electrical double layer capacitance Cp of the electrode/membrane can be found according to the formula for the angular frequency of the highest point of the semicircle. Then according to RΩAnd the areas of the electrode ends of the first lead wire 4 and the second lead wire 7, the conductivity of the film is calculated as follows:
in the formula, the S electrode is the area of the end face of the upper tapered electrode 3 (or the electrode end of the lead 7), and d is the thickness of the film to be measured.
The measuring method specifically comprises the following steps:
A. selecting electrodes and lead I4, lead II7 and proton exchange membrane 6 sample sheets which meet the standard;
B. the weight table 1 is lifted up through the needle-shaped electrode shaft 2, the fastening screws of the pressure-permeable plate 5 and the insulating base 12 are loosened, and the pressure-permeable plate 5 is taken down.
C. Spreading the proton exchange membrane 6 to be tested on the insulating base 12 to completely cover the electrode of the lead II7 on the insulating base 12, flatly pressing the pressure permeable plate 5 with the air permeable through hole 9 on the proton exchange membrane 6 to be tested, slowly dropping the needle-shaped electrode shaft 2 lined with the lead I4 and lightly pressing the needle-shaped electrode shaft on the film to be tested;
D. a weight with the mass of 80g is placed on the weight table 1 on the needle-shaped electrode shaft 2, the mass of the weight pressurizes the needle-shaped electrode shaft 2, and the electrode end plane of the lead I4 and the electrode end plane of the lead II7 are ensured to be stacked together with the proton exchange membrane 6 to be tested between the two, and the proton exchange membrane 6 to be tested has no folds.
E. Placing the testing device with the proton exchange membrane 6 installed in a constant temperature and humidity box, clamping a lead I4 and a lead II7 by metal clamps in the constant temperature and humidity box respectively, and then connecting an electrode of an electrochemical workstation with a power supply connection outside the constant temperature and humidity box; starting an alternating current impedance test program, measuring and reading an impedance value and calculating the conductivity.
Wherein, the cone-shaped electrode 3 vertically moves up and down above the cylindrical electrode to fasten the proton exchange membrane 6. The contact state of the electrode and the proton exchange membrane 6 can be accurately controlled by adding weights on the weight table 1, and uncertainty and instability of influence factors such as contact resistance, electric double-layer capacitance resistance of the electrode and the proton exchange membrane 6 and the like during measurement are reduced; the insulating high-frequency low-dielectric material can play an insulating effect, a non-test area of a sample to be tested does not need to be subjected to insulating treatment, and the influence of electrochemical impedance and capacitive reactance of equipment in the test can be neglected due to the extremely low dielectric constant. Through the high-precision electrochemical workstation, voltage and current data in a test loop can be accurately tested, and the accuracy of a test result is improved. Alternating current is applied to the two sides of the proton exchange membrane 6 through the inert electrodes, an alternating current impedance spectrogram is drawn, the spectrogram is analyzed to obtain the transverse resistance of the fuel cell membrane, and the conductivity of the proton exchange membrane 6 in the membrane thickness direction is further calculated through the effective areas of the membrane and the inert electrodes and the thickness of the membrane to be measured.
The step A specifically comprises the following steps: a, measuring the areas S1 and S2 of the electrode end of the lead wire I4 and the electrode end of the lead wire II7, so that S1-S2 is less than 0.005S 1;
b, placing the electrode end of the lead I4 and the electrode end of the lead II7 in a 5% dilute nitric acid solution for soaking for 24 hours to remove organic stains or impurity metal particles on the surface of the electrode;
c, setting parameters of the constant temperature and humidity box to be in an environmental condition of a certain temperature and humidity, and standing for 2 hours;
d, selecting the proton exchange membrane 6 to be tested, cutting the proton exchange membrane into sample pieces, wherein the sample pieces are smaller than the transparent pressing plate 5 on the device, and the length and the width of each sample piece are respectively smaller than 5mm of the length and the width of the transparent pressing plate 5, so that the proton exchange membrane 6 is ensured not to be damaged by the fixing screws of the insulating base 12.
The step E specifically comprises the steps of measuring an impedance map of the proton exchange membrane 6 applied between the conical electrode 3 and the cylindrical electrode in the frequency range of 1-10MHz and the small-amplitude sine wave disturbance potential amplitude of 100mV through an electrochemical workstation, calculating the conductivity of the proton exchange membrane 6 of the fuel cell membrane in the membrane thickness direction according to an equivalent circuit and a conductivity formula, changing the contact pressure of the conical electrode 3 by adjusting the weight and the number of weights on the weight tray 1, reducing the influence of the contact resistance on a measurement result, polishing the electrode end of the lead I4 and the electrode end of the wire II7 on polishing cloth by 0.05 mu m of α -Al2O3, and sequentially performing ultrasonic treatment on acetone and water for 10-100min to ensure the contact state of the electrodes and the film to be measured.
Example 2:
detection preparation: and measuring the areas S1 and S2 of the electrode end of the lead I4 and the electrode end of the lead II7, calculating the difference value of the two, wherein the difference value (S1-S2) is less than 0.005S1, and if the difference value is too large, processing the larger electrode end until the requirements are met. Meanwhile, the surface smoothness of the electrode end of the lead I4 and the electrode end of the lead II7 is checked, and the end faces are smooth and have no protruding points or sunken points.
Checking the surface integrity of the film to be detected, observing under natural light or fluorescent lamp or magnifying glass by means of a magnifying device, if obvious defects (wrinkles, stains, pinholes and creases) are found in the appearance, abandoning the film and preparing a sample by taking the sample to be detected again.
Pretreatment of the platinum electrode: before testing, the electrode terminal of the lead I4 and the electrode terminal of the lead II7 are soaked in a 5% dilute nitric acid solution for 24 hours to remove organic stains or impurity metal particles on the surface of the electrodes. The parameters of the constant temperature and humidity chamber are set as follows: the temperature is 30 ℃, the relative humidity is 20% RH, 40% RH, 60% RH, 80% RH, 90% temperature and humidity environment, standing is carried out for 2h, so that the proton exchange membrane 6 is fully swelled, and then the thickness is measured by using a thickness gauge.
The proton exchange membrane 6 to be tested is selected and cut into sample pieces, the sample pieces are smaller than the area of the device permeation pressure plate 5 (the length and the width are respectively smaller than 5mm of the length and the width of the permeation pressure plate), and the proton exchange membrane 6 is ensured not to be damaged by the fixing screws on the device insulation base 12. And lifting the weight table upwards through the needle-shaped electrode shaft 2 by the aid of the weight table 1, loosening fastening screws of the insulating transparent pressing plate 5 and the insulating base 12, and taking down the transparent pressing plate 5.
The film to be measured is laid on the insulating base 12 to completely cover the electrode of the lead II7 on the insulating base 12, then the pressure-permeable plate 5 with the air-permeable through hole 9 is pressed on the film to be measured, and the needle-shaped electrode shaft 2 lined with the lead I4 slowly falls down and is lightly pressed on the film to be measured. A weight with the mass of 80g is placed on the weight table 1 on the needle-shaped electrode shaft 2, the weight presses the needle-shaped electrode shaft 2, and the electrode end plane of the lead I4 and the electrode end plane of the lead II7 are stacked together with the film to be detected between the electrode end plane and the lead II7, so that the film to be detected is not wrinkled.
The device with the film installed is placed in a constant temperature and humidity box, a lead I4 and a lead II7 are respectively clamped by metal clamps inside the device, and then electrodes of the electrochemical workstation are connected with power supply wiring outside the constant temperature and humidity box (a red connector is inserted into a green electrode wiring terminal, and a black connector is inserted into a blue electrode wiring terminal). Starting an alternating current impedance test program, measuring and reading an impedance value and calculating the conductivity. From the read resistance value, the conductivity calculation formula is substituted:
k membrane conductivity (mS/cm)
d: thickness of the film
RΩ+Rp: measured impedance value (k.OMEGA.) of the sample
SElectrode for electrochemical cell: end area S1 of electrode end of lead I4 or end area S2 of electrode end of lead II7
Starting an alternating-current impedance test program for measurement, finishing the test, deriving measurement data in the electrochemical workstation, inputting the measurement data into origin data processing software to make a vertical resistance temperature and humidity characteristic curve as shown in fig. 6.
Example 3:
example 3 differs from example 2 in that: the temperature of the constant temperature and humidity chamber in the steps in the example is set to 80 ℃, the relative humidity is respectively the temperature and humidity environment of 20% RH, 40% RH, 60% RH, 80% RH, 90%, the electrical conductivity is measured and calculated, and the temperature and humidity electrical conductivity characteristic curve at 80 ℃ is drawn as shown in fig. 7.
Claims (10)
1. A device for measuring the conductivity of a proton exchange membrane in the thickness direction is characterized by comprising an insulating base (12), a supporting frame is arranged on the insulating base (12), a baffle plate is arranged above the supporting frame, the center of the baffle is provided with a linear bearing, the needle-shaped electrode shaft (2) moves vertical to the insulating base (12) under the restriction of the linear bearing, a weight table (1) is arranged at the top end of the needle-shaped electrode shaft (2) above the baffle, the bottom of the needle-shaped electrode shaft (2) below the baffle is provided with a conical electrode (3), a transparent pressing plate (5) is arranged on the insulating base (12) below the conical electrode (3), a cylindrical electrode is arranged on the insulating base (12) below the transparent pressing plate (5), a proton conducting membrane (6) is laid between the cylindrical electrode and the pressure permeable plate (5), the cone-shaped electrode (3) can vertically move up and down above the pressure transmission plate (5) to fasten the proton conduction membrane (6).
2. The device for measuring the electrical conductivity of the proton exchange membrane in the membrane thickness direction according to claim 1, wherein the conical electrode (3) comprises a conical body, a circular pore channel (13) with the diameter of 0.8-1 mm is arranged in the conical body, and a lead I (4) penetrates through and is fixed in the circular pore channel (13) along the central line direction to form the electrode;
the conical electrode (3) and the needle-shaped electrode shaft (2) move perpendicular to the insulating base (12) under the restraint of a linear bearing, the distance from the surface of the cylindrical electrode to the surface of the cylindrical electrode is 100mm when the needle-shaped electrode shaft (2) moves to the highest point, and the conical electrode (3), the proton exchange membrane (6) and the cylindrical electrode are clamped to form an electrochemical system electrode when the needle-shaped electrode shaft (2) moves to the lowest point.
3. The device for measuring the film thickness direction conductivity of the proton exchange membrane according to claim 1, wherein the cylindrical electrode comprises a groove which is arranged on the insulating base (12), and the groove is cylindrical with the depth of 2mm and the diameter of 2 mm; and a lead II (7) and an electrode end thereof are embedded in the groove, the center of the electrode end face of the lead II (7) is vertically aligned with the electrode end face of the lead I (4) after the installation is finished, and the other ends of the lead I (4) and the lead II (7) are connected with an electrochemical workstation.
4. The device for measuring the conductivity of the proton exchange membrane in the membrane thickness direction according to claim 1, wherein the transparent plate (5) is rectangular, a conical groove is formed in the center of the transparent plate (5), vertical ventilation through holes (9) are formed in a conical inclined plane of the conical groove, the diameter of each through hole (9) is less than 2mm, and the number of the through holes (9) is less than 30; the conical inclined plane of the pressure transmission plate (5) is consistent with the conical taper of the conical body.
5. The device for measuring the membrane thickness direction conductivity of the proton exchange membrane according to claim 1, wherein the permeable plate (5) is provided with positioning holes (14) at the peripheral edge, the insulating base (12) is provided with openings (8) corresponding to the positioning holes (14), and the diameter of each opening (8) is larger than that of a fastening bolt by 1 mm; the relative position deviation between the positioning hole (14) and the opening (8) on the insulating base (12) is not more than 1 mm.
6. The device for measuring the electrical conductivity of the proton exchange membrane in the membrane thickness direction according to claim 1, wherein positioning grooves (10) are formed in two sides of the pressure-permeable plate (5), positioning blocks (11) corresponding to the positioning grooves (10) are formed in the insulating base (12), and the pressure-permeable plate (5) and the insulating base (12) are fixed through fastening bolts.
7. The device for measuring the conductivity of the proton exchange membrane in the membrane thickness direction according to claim 1, wherein the needle-shaped electrode shaft (2), the cylindrical electrode, the pressure permeable plate (5) and the insulating base (12) are made of polyetheretherketone, polytetrafluoroethylene or PET polymer non-conductive materials;
the lead I (4) and the lead II (7) are made of platinum, gold-plated copper and silver with low resistivity;
the volume resistivity of the non-conductive material is 900-1100 omega cm.
8. A method for measuring the conductivity of a proton exchange membrane in the membrane thickness direction by using the method as claimed in claims 1 to 7, comprising the following steps:
A. selecting electrodes and lead I (4), lead II (7) and proton exchange membrane (6) sample sheets which meet the standard;
B. the weight table (1) is lifted upwards through the needle-shaped electrode shaft (2), the fastening screws of the pressure permeable plate (5) and the insulating base (12) are loosened, and the pressure permeable plate (5) is taken down.
C. Spreading a proton exchange membrane (6) to be tested on an insulating base (12) to completely cover an electrode of a lead II (7) on the insulating base (12), flatly pressing a pressure transmission plate (5) with a ventilation through hole (9) on the proton exchange membrane (6) to be tested, and slowly dropping a needle-shaped electrode shaft (2) lined with a lead I (4) to lightly press on a film to be tested;
D. weights are placed on a weight table (1) on the needle-shaped electrode shaft (2), the weight applies pressure to the needle-shaped electrode shaft (2), the electrode end plane of the lead I (4), the electrode end plane of the lead II (7) and the proton exchange membrane (6) to be tested between the electrode end plane and the lead II are stacked together, and the proton exchange membrane (6) to be tested does not have wrinkles.
E. Placing the testing device with the proton exchange membrane (6) installed in a constant temperature and humidity box, clamping a lead I (4) and a lead II (7) by using metal clamps in the constant temperature and humidity box respectively, and then connecting an electrode of an electrochemical workstation with a power supply wiring outside the constant temperature and humidity box; starting an alternating current impedance test program, measuring and reading an impedance value and calculating the conductivity.
9. The method for measuring the conductivity of the proton exchange membrane in the membrane thickness direction according to claim 8, wherein the step a specifically comprises the following steps: a, measuring the areas S1 and S2 of the electrode end of the lead I (4) and the electrode end of the lead II (7) to enable S1-S2 to be less than 0.005S 1;
b, placing the electrode end of the lead I (4) and the electrode end of the lead II (7) in a 5% dilute nitric acid solution for soaking for 24 hours to remove organic stains or impurity metal particles on the surface of the electrodes;
c, setting the parameters of the constant temperature and humidity box into environmental conditions of temperature and humidity, and standing for 2 hours;
d, selecting a proton exchange membrane (6) to be tested, cutting the proton exchange membrane into sample pieces, wherein the sample pieces are smaller than a transparent pressing plate (5) on the device, and the length and the width of each sample piece are respectively smaller than 5mm of the length and the width of the transparent pressing plate 5, so that the proton exchange membrane (6) is ensured not to be damaged by fixing screws of an insulating base (12).
10. The method for measuring the conductivity of the proton exchange membrane in the membrane thickness direction as claimed in claim 8, wherein the step E specifically comprises measuring an impedance spectrum of the proton exchange membrane (6) applied between the cone-shaped electrode (3) and the cylindrical electrode in the frequency range of 1-10MHz and the small amplitude sine wave perturbation potential amplitude of 100mV through an electrochemical workstation, calculating the conductivity of the proton exchange membrane (6) in the membrane thickness direction of the fuel cell membrane according to an equivalent circuit and a conductivity formula, changing the contact pressure of the cone-shaped electrode (3) by adjusting the weight and the number of weights on the weight tray (1), and reducing the influence of the contact resistance on the measurement result, wherein the electrode end of the lead I (4) and the electrode end of the wire II (7) are polished on a polishing cloth by using α -Al2O3 of 0.05 μm, and are sequentially subjected to ultrasonic treatment in acetone and water for 10-100min to ensure the contact state of the electrodes and the membrane to be measured.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910994068.9A CN110988480A (en) | 2019-10-18 | 2019-10-18 | Device and method for measuring conductivity of proton exchange membrane in thickness direction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910994068.9A CN110988480A (en) | 2019-10-18 | 2019-10-18 | Device and method for measuring conductivity of proton exchange membrane in thickness direction |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110988480A true CN110988480A (en) | 2020-04-10 |
Family
ID=70082127
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910994068.9A Withdrawn CN110988480A (en) | 2019-10-18 | 2019-10-18 | Device and method for measuring conductivity of proton exchange membrane in thickness direction |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110988480A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113267680A (en) * | 2021-07-15 | 2021-08-17 | 国家电投集团氢能科技发展有限公司 | Proton exchange membrane conductivity test chamber and test method |
-
2019
- 2019-10-18 CN CN201910994068.9A patent/CN110988480A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113267680A (en) * | 2021-07-15 | 2021-08-17 | 国家电投集团氢能科技发展有限公司 | Proton exchange membrane conductivity test chamber and test method |
| CN113267680B (en) * | 2021-07-15 | 2022-01-07 | 国家电投集团氢能科技发展有限公司 | Proton exchange membrane conductivity test chamber and test method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Soboleva et al. | Investigation of the through-plane impedance technique for evaluation of anisotropy of proton conducting polymer membranes | |
| CN105486927B (en) | A kind of measuring method of solid insulating material specific insulation | |
| CN104678173A (en) | Testing method for area resistance of diaphragm of lithium battery | |
| US10054561B2 (en) | Device for detection of ionic conductivity and its applied measurement | |
| CN206362861U (en) | A kind of resistance testing device of electrodes of lithium-ion batteries coating material | |
| CN107247184A (en) | The test device and method of testing of a kind of electrical conductivity | |
| CN107290399B (en) | Transformer water content measuring device based on PDC/FDS medium response method | |
| CN112903537A (en) | Method for testing battery cell wettability | |
| CN110988480A (en) | Device and method for measuring conductivity of proton exchange membrane in thickness direction | |
| CN110061270A (en) | The non-destructive measuring method of fuel battery double plates and carbon paper interface contact resistance | |
| CN107219400A (en) | Solid electrolyte ion conductivity test jig, system and method | |
| CN213275763U (en) | Device for measuring conductivity of proton conducting membrane in thickness direction | |
| CN105759123B (en) | A kind of ionic conductivity test device and use its method of testing | |
| CN114136878A (en) | Method for testing corrosion resistance of fuel cell metal bipolar plate coating | |
| CN203688666U (en) | Lithium battery diaphragm area resistance testing device | |
| CN105158570A (en) | Simple method for testing electrical conductivity of solid electrolyte | |
| CN108562624A (en) | A kind of method and device measuring plant leaf blade intrinsic water storage gesture and intrinsic water storage power | |
| CN113009364A (en) | Method for measuring alternating current impedance of failure battery | |
| CN205103317U (en) | Measurement device for solid insulating material volume resistivity | |
| CN113075255B (en) | Lithium battery diaphragm thermal shrinkage test method and test equipment | |
| CN205861590U (en) | Electrodes of lithium-ion batteries thermal conductivity consistency detection device | |
| US20090039893A1 (en) | Electrolyte measurement device and measurement procedure | |
| CN211718476U (en) | Solid-state battery rapid measuring device | |
| CN209043174U (en) | A kind of lighium polymer cell polar ear spacing and back gauge detection device | |
| CN111060563B (en) | Device and method for identifying doping of gold bricks through resistivity |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information |
Address after: 256401 Dongyue fluorosilicone Material Industrial Park, Tangshan Town, Huantai, Zibo, Shandong Applicant after: Shandong Dongyue future hydrogen energy materials Co.,Ltd. Address before: 256401 Dongyue fluorosilicone Material Industrial Park, Tangshan Town, Huantai, Zibo, Shandong Applicant before: Shandong Dongyue future hydrogen energy materials Co.,Ltd. |
|
| CB02 | Change of applicant information | ||
| CB03 | Change of inventor or designer information |
Inventor after: Lu Guowei Inventor after: Zou Yecheng Inventor after: Zhang Zunbiao Inventor after: Zhang Yongming Inventor before: Lu Guowei Inventor before: Zou Yecheng Inventor before: Zhang Zunbiao Inventor before: Feng Wei Inventor before: Zhang Yongming |
|
| CB03 | Change of inventor or designer information | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20200410 |
|
| WW01 | Invention patent application withdrawn after publication |