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CN-122017348-A - Combined device and method for measuring surface resistance and bubble point of alkaline hydrogen production diaphragm

CN122017348ACN 122017348 ACN122017348 ACN 122017348ACN-122017348-A

Abstract

A combined device and method for measuring the surface resistance and bubble point of alkaline hydrogen-producing membrane comprises an end plate assembly with a transparent observation window, a first electrolyte containing cavity and a second electrolyte containing cavity which are respectively positioned at two sides of the membrane, a membrane fixing plate for clamping the membrane and limiting an effective test area, an electrode plate with a central opening, a multi-layer sealing gasket and a fastening assembly, and a liquid injection/liquid discharge interface, a liquid discharge interface and an air inlet interface. The transparent observation window is used for observing the infiltration state of the diaphragm and the bubble generation and attachment behaviors in real time, so that the accuracy of judging the surface resistance and the bubble point is improved, and a consistent microscopic state basis is provided for establishing the association between the bubble point and the area resistance.

Inventors

  • ZHANG WENJUAN
  • LIU GANG

Assignees

  • 合肥膜钧科技有限公司

Dates

Publication Date
20260512
Application Date
20260212

Claims (9)

  1. 1. The combined device and method for measuring the surface resistance and bubble point of the alkaline hydrogen production membrane are characterized by comprising an insulating transparent end plate (15), a first insulating electrolyte containing cavity (1) and a second insulating electrolyte containing cavity (13), a first electrode plate (3) and a second electrode plate (11), a first membrane fixing plate (5) and a second membrane fixing plate (9), a multi-layer sealing gasket (2, 4, 6, 8, 10, 12, 14) and a fastening component; The insulating transparent end plate (15) is used for sealing and providing a test window so that a tester can directly observe the air bubble distribution condition in the device, and the lower part of the end plate is provided with a liquid discharge valve (18); the first and second insulating electrolyte containing cavities (1, 13) are respectively positioned at two sides of the diaphragm to be tested, and the middle part of the first and second insulating electrolyte containing cavities is provided with a through hole and an electrolyte inlet and outlet interface; The first electrode plate (3) and the second electrode plate (11) are respectively arranged at the inner sides of the first accommodating cavity (1) and the second accommodating cavity (13), the first electrode plate (3) and the second electrode plate (11) are respectively provided with a lug for electric connection, and the central area of the first electrode plate and the second electrode plate is provided with a netlike through hole structure; the first diaphragm fixing plate (5) and the second diaphragm fixing plate (9) are used for clamping the diaphragm to be tested and limiting an effective test area; the multi-layer sealing gaskets (2, 4,6, 8, 10, 12, 14) are arranged between adjacent components to realize sealing; The fastening assembly comprises an insulating bolt (16) and a nut (17) and is used for compacting the components along the thickness direction to form a closed test cavity; The device can perform surface resistance measurement in an electrolyte environment under the condition of keeping the clamping and compressing states of the diaphragm unchanged through valve path switching of the liquid discharge valve (18) and the air inlet (19), and perform bubble point pressure measurement after the second containing cavity (13) is emptied, and the transparent observation window is used for visually observing bubble point generation and bubble attachment behaviors.
  2. 2. The testing device according to claim 1, wherein the thickness of the insulating transparent end plate (15) is 10-20 mm, the thickness of the insulating electrolyte containing cavity (1, 13) is 5-20 mm, the thickness of the diaphragm fixing plate (5, 9) is 2-5 mm, the thickness of the electrode plate (3, 11) is 0.3-1.0 mm, the thickness of the insulating sealing gasket is 0.2-0.5 mm, and the size of the bolt is larger than the thickness of each part stacked together.
  3. 3. Testing device according to claim 1 or 2, characterized in that the centers of the first and second cavities (1, 13) are provided with through holes coaxial with the through holes of the diaphragm fixing plate, and the through holes have the same size and smaller than the outline size of the diaphragm to be tested, so that the effective testing area is defined by the through holes.
  4. 4. A test device according to any one of claims 1 to 3, characterized in that the insulating transparent end plate (15) is provided with an air inlet/outlet/liquid pipeline, the pipeline is provided with a liquid discharge valve, the end plate material is selected from transparent materials such as polymethyl methacrylate, perfluoroethylene propylene, polycarbonate and the like, the first insulating electrolyte containing cavity (1) and/or the second insulating electrolyte containing cavity (13) are provided with an air inlet/outlet, the materials are selected from polytetrafluoroethylene, the materials of the first diaphragm fixing plate (9) and/or the second diaphragm fixing plate (5) are selected from polytetrafluoroethylene, the sealing gasket material is selected from one or more of polytetrafluoroethylene films, polyether ether ketone films or polyphenylene sulfide films, and the fastening component is an insulating fastening piece, and the materials of the fastening piece are selected from polyether ether ketone or polyphenylene sulfide.
  5. 5. A test device according to any one of claims 1 to 3, wherein the central openings of the first electrode sheet (3) and/or the second electrode sheet (11) are in a grid-like or porous array structure to facilitate gas-liquid mass transfer, and the electrode sheet material is selected from one or more of nickel, nickel alloy, stainless steel or titanium.
  6. 6. A test device according to any one of claims 1 to 3, wherein the air inlet (19) is in communication with an external air supply system comprising an air source A, a flow regulating member B, a pressure monitoring member C and a safety pressure relief member D.
  7. 7. A method for determining the area resistance and bubble point pressure of an alkaline electrolyzed water membrane using the test apparatus of any one of claims 1 to 7, comprising the steps of: (1) Membrane pretreatment, namely soaking a membrane to be tested in alkaline solution to fully wet the membrane; (2) The assembly comprises stacking an end plate assembly (15), a sealing gasket, a first containing cavity (1), a sealing gasket, a first electrode plate (3), a sealing gasket, a first diaphragm fixing plate (5), a sealing gasket, a diaphragm to be tested, a sealing gasket, a second diaphragm fixing plate (9), a sealing gasket, a second electrode plate (11), a sealing gasket and a second containing cavity (13) in sequence, and uniformly fastening to form a closed test cavity with a torque of 2-5N m; (3) Electrochemical testing, namely respectively injecting electrolyte into the first accommodating cavity (1) and the second accommodating cavity (13), connecting electrode lugs with an electrochemical workstation, and testing by adopting an alternating current impedance method, wherein the frequency range is 1 Hz-10 6 Hz; (4) Data processing, namely reading real axis intercept of high-frequency end of Nyquist diagram to calculate resistance value according to formula R A =(R Z R 0 ) multiplied by A, wherein R Z is a test resistor with a diaphragm, R 0 is a blank device resistor, A is an effective test area, and R A is calculated as the surface resistance of the diaphragm under a specific atmosphere. (5) Medium emptying, namely opening a liquid discharge valve to completely discharge alkali liquor in the second insulating electrolyte containing cavity (13), and keeping the assembly state of the device unchanged; (6) The air tightness inspection, namely inspecting the air tightness and the liquid tightness of the nylon plastic pipe connection at each interface of the peripheral pipeline system; (7) The bubble point test comprises the steps of maintaining the alkali liquor in the first insulating electrolyte containing cavity (1) unchanged or changing the alkali liquor into pure water or n-butyl alcohol medium, enabling the liquid injection quantity to just fill the first insulating electrolyte containing cavity (1), connecting an air circuit system to slowly ventilate and pressurize the other side of the diaphragm, and recording a pressure value when the first continuous bubbles are observed to be generated on the surface of the diaphragm, namely the bubble point.
  8. 8. The method of claim 7, wherein the electrolyte is an alkaline electrolyte and is a base alkaline solution or a saturated gas-containing electrolyte pre-bubbled with oxygen or hydrogen to simulate a gas-liquid two-phase environment of the electrolyzer when the surface resistance is measured.
  9. 9. The method of claim 7 or 8, wherein the test temperature is controlled to be 25-80 ℃, the electrochemical test parameters are set to be 10 mV as the alternating current disturbance amplitude and 10 6 Hz to 1Hz as the frequency scanning range under the condition of open circuit potential.

Description

Combined device and method for measuring surface resistance and bubble point of alkaline hydrogen production diaphragm Technical Field The invention belongs to the technical field of alkaline water electrolysis hydrogen production diaphragm testing and evaluation, and particularly relates to a device and a method capable of in-situ measuring the surface resistance and bubble point pressure of an alkaline water electrolysis diaphragm in the same clamping and pressing state under the assistance of a visual means in a controllable atmosphere environment. Background The area resistance and bubble point pressure of the alkaline electrolyzed water diaphragm are two key indexes for representing the service performance of the diaphragm. The area resistance reflects the obstruction degree of the diaphragm to OH - conduction and directly influences the energy consumption of the electrolytic cell, and the bubble point pressure characterizes the gas barrier capacity and pore size distribution characteristics of the diaphragm and is an important basis for evaluating the operation safety boundary. In the research and development process, the two parameters are accurately acquired and the corresponding relation is established, so that the optimization of the diaphragm formula, the microstructure and the process window is guided. At present, the area resistance and the bubble point pressure are usually measured in a separation mode, namely the area resistance is obtained in an electrochemical cell by means of electrochemical impedance spectroscopy, and the bubble point pressure is measured in a separate bubble point testing device/instrument. Because the two types of testing devices have differences in boundary conditions such as electrode structures, clamping modes, compression stress distribution, wetting modes, testing medium states and the like, if the same diaphragm is adopted, microporous deformation, compression state change or coating/fiber structure damage is easily caused by repeated disassembly and assembly, and if different diaphragms are adopted, the two types of testing devices are influenced by sample non-uniformity, and the two types of testing devices are difficult to ensure that the two types of testing devices correspond to the same microscopic state. On the other hand, most of the test cavities are of opaque structures, the test process is invisible, the infiltration degree of the diaphragm and the adhesion condition of bubbles on the surface of the diaphragm cannot be observed, and the specific influence of the bubbles on actual parameter measurement is difficult to quantify, so that the consistency of a test result and actual gas-liquid two-phase working conditions is reduced. Therefore, a comprehensive testing device and method capable of realizing in-situ combination of area resistance and bubble point pressure in the same clamping state and performing visual observation on the membrane infiltration and bubble generation processes are needed. Disclosure of Invention In order to overcome the problems in the prior art, the invention provides a visual in-situ combined testing device and method for the surface resistance and bubble point of an alkaline electrolytic water diaphragm, and aims to solve the problems of single testing environment, invisible process, poor comparability of results caused by step-by-step testing and the like in the prior art. According to the method, by adopting the high-pressure-resistant transparent end plate and the integrated sealing design and matching with the controllable gas-liquid switching system, the surface resistance and bubble point of the same diaphragm are sequentially tested in the same clamping state, on one hand, secondary assembly errors are eliminated by utilizing in-situ testing, on the other hand, by utilizing visual observation, the resistance change in a real electrolysis environment (containing bubble electrolyte) can be simulated and observed, and the instant generated by the bubble point can be accurately captured by naked eyes or a camera, so that high-precision and high-relevance diaphragm performance data can be obtained. Specifically, in order to achieve the aim, the visual in-situ combination testing device for measuring the surface resistance and bubble point pressure of the alkaline electrolyzed water diaphragm comprises an insulating transparent end plate (15), a first insulating electrolyte containing cavity (1) and a second insulating electrolyte containing cavity (13), a first electrode plate (3) and a second electrode plate (11), a first diaphragm fixing plate (5) and a second diaphragm fixing plate (9), a multi-layer sealing gasket (2, 4, 6, 8, 10, 12, 14) and a fastening assembly; The insulating transparent end plate (15) is used for sealing and providing a test window, and the lower part of the end plate is provided with a liquid discharge valve (18); the first and second insulating electrolyte containing cavities (1, 13) are respectiv