A bipolar electrochemical test cell structure and method for testing catalytic electrode performance and continuous test cell voltage

Abstract

The present application relates to a kind of bipolar electrochemical test cell structure and its method for testing catalytic electrode performance and continuously testing cell voltage, belong to electrochemical performance detection technical field.The test cell structure of the present application includes N test channels, each test channel includes continuously arranged M grooves, the groove wall at the junction of adjacent two grooves is made of insulating material, and a plurality of clamping slots are symmetrically opened on the opposite two side walls in each groove, N≥2, M≥3.The test cell can be used to continuously test the performance of catalytic electrode under several electrolytic cells, and the external voltage growth after continuously stacking several electrolytic cells, and then calculate the cell voltage.The test cell and analysis method can simulate the working mode of bipolar electrolytic cell catalytic electrode wireless connection under real working condition, more truly reflect the catalytic performance of catalytic electrode under wireless connection mode, and can also provide data support and theoretical basis for the design of bipolar electrolytic cell cell number and cell voltage.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical performance testing technology, specifically relating to a bipolar electrochemical test cell structure and its method for testing the performance of catalytic electrodes and continuously testing the chamber voltage. Background Technology

[0002] Against the backdrop of a global effort to address climate change and accelerate energy transition, hydrogen energy, as a clean, efficient, and sustainable secondary energy source, is hailed as the "ultimate energy of the 21st century" and is gradually becoming a focal point in the energy sector. Among these methods, water electrolysis for hydrogen production, with its ability to be closely integrated with renewable energy sources and its near-zero carbon emissions, has become a major method for producing green hydrogen and has attracted widespread attention.

[0003] Electrolysis of water to produce hydrogen, simply put, is the process of using electrical energy to decompose water into hydrogen and oxygen. Its basic principle follows the electrolysis law in electrochemistry. In an electrolytic cell, when direct current passes through an aqueous electrolyte solution, oxygen is produced by oxidation at the anode due to the loss of electrons, while hydrogen is produced by reduction at the cathode due to the gain of electrons.

[0004] Taking an alkaline electrolyte solution as an example, the two half-reactions are:

[0005] Hydrogen Evolution Reaction (HER):

[0006]

[0007] Oxygen Evolution Reaction (OER):

[0008]

[0009] Overall chemical reaction equation:

[0010]

[0011] Under standard conditions (25℃, 1 atm), the theoretical decomposition voltage for water electrolysis is 1.23V. In actual electrolysis, the applied voltage needs to be higher than the theoretical decomposition voltage, where the hydrogen evolution overpotential (η) is a factor. HER ) and oxygen evolution overpotential (η) OER This was a major reason.

[0012] In the process of water electrolysis, the core role of the catalyst is to reduce the overpotential of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), thereby accelerating the reaction rate and improving energy conversion efficiency. The catalytic electrode is an electrode with a catalyst loaded on its surface. It typically uses a conductive substrate such as a nickel mesh or titanium mesh, and a layer of catalyst is coated onto its surface through processes such as electrodeposition, electrospraying, or magnetron sputtering to form the final catalytic electrode. It is the core component of the electrocatalytic reaction, and its function is to achieve highly efficient catalysis of the electrocatalytic reaction by regulating interfacial electron transfer and lowering the activation energy of the reaction.

[0013] In the electrolyzer design phase, evaluating the catalytic activity of the catalytic electrode is of significant scientific importance for reducing DC power consumption and improving electrolysis efficiency. The existing laboratory method for evaluating the catalytic activity of the catalytic electrode is based on the traditional three-electrode system and linear sweep voltammetry (LSV) curves, using a 10 mA / cm² value from the LSV curve. 2 The overpotential corresponding to the current density is the main evaluation index. Traditional three-electrode testing systems use a catalytic electrode as the working electrode (WE), a saturated calomel electrode (or silver / silver chloride, mercury / mercury oxide, etc.) as the reference electrode (RE), a platinum sheet (or carbon rod, etc.) as the counter electrode (CE), and a round beaker as the electrolytic cell. Figure 1 A. Actual electrolytic cells, based on their electrical connection method, can be divided into single-pole electrolytic cells (…). Figure 1 (B) and bipolar electrolytic cell ( Figure 1 (C) In a unipolar electrolyzer, each anode electrode is directly connected to the positive terminal of an external DC power supply, and each cathode is directly connected to the negative terminal. The electrodes are connected in parallel. The electrolyzer operates under high current and low voltage, resulting in low electrolysis efficiency and high DC power consumption. In contrast, in a bipolar electrolyzer, only the anodes and cathodes at both ends are directly connected to the positive and negative terminals of the external DC power supply. Electrons are continuously transferred through a conductive bipolar plate in the middle. Under the combined potential of the anode and cathode plates, the bipolar plate evenly divides the electrolyzer into N small chambers, each chamber forming an electrolytic cell with an anode and a cathode. The electrodes in the middle are electrically connected to the bipolar plate to achieve electron transfer and conduct redox reactions. The two sides of the bipolar plate are the anode side and the cathode side, hence the name bipolar plate. Due to its compact design and efficient current transmission method, bipolar electrolyzers typically have lower unit costs and are more cost-effective in large-scale hydrogen production applications. Therefore, most electrolyzers on the market are bipolar electrolyzers. However, existing methods for evaluating the performance of catalytic electrodes based on a three-electrode system are closer to the working mode of catalytic electrodes in a unipolar electrolyzer and cannot truly reflect the working performance of catalytic electrodes in a bipolar electrolyzer.

[0014] The cell voltage directly determines the DC power consumption of the electrolyzer; the higher the cell voltage, the higher the DC power consumption. Cell voltage is the "core dashboard" of the electrolysis process—it is not only a "ruler" for energy consumption control, but also a "barometer" for process stability and a "microscope" for fault diagnosis, directly determining the economic efficiency, safety, and equipment reliability of production. For the water electrolysis industry, precise control of cell voltage is a core technical means to achieve "high efficiency, low consumption, and long-cycle operation."

[0015] Existing methods for testing catalytic electrode performance and chamber voltage have the following problems:

[0016] 1. Based on the three-electrode system, additional reference electrodes (mercury / mercury oxide reference electrodes) and counter electrodes (platinum sheet electrodes) are required during testing, which makes the experimental conditions more demanding.

[0017] 2. Based on the three-electrode system, the potential value obtained by the test is relative to the reference electrode potential. Subsequent data processing needs to be converted to a relative reversible hydrogen electrode, which is cumbersome and complex, and is prone to data processing errors.

[0018] 3. Based on the three-electrode system, the potential impact of the counter electrode on the performance of the working electrode is ignored, and the characterized performance cannot truly reflect the performance of the catalytic electrode in actual electrolytic cell operation.

[0019] 4. A single electrolysis cell cannot continuously test the changes in the performance of the catalytic electrode after several electrolysis cells are stacked together, nor can it measure the increase in the total external voltage that needs to be applied to the entire electrolysis cell after stacking.

[0020] 5. The design of the number of electrolytic cell chambers lacks data support. Summary of the Invention

[0021] To address the technical problems existing in the prior art, this invention provides a bipolar electrochemical test cell structure and a method for testing the performance of catalytic electrodes and continuously testing the cell voltage. The performance of the catalytic electrode tested by this invention can more closely reflect the actual performance of the catalytic electrode in actual electrolytic cell operation, and it does not require additional reference electrodes and counter electrodes, simplifying experimental testing conditions and eliminating the need for complex data processing. The method for continuously testing the cell voltage of this invention provides data support and basis for designing the number of cells and the cell voltage in electrolytic cells.

[0022] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows.

[0023] In a first aspect, the present invention provides a bipolar electrochemical test cell structure, including N test channels, each test channel including M grooves arranged in succession, the wall of the groove at the connection between two adjacent grooves is made of insulating material, and several slots are symmetrically opened on the two opposite side walls of each groove, N≥2, M≥3.

[0024] Preferably, the N test channels are arranged consecutively, and the groove walls at the connection between two adjacent test channels are made of insulating material.

[0025] Preferably, the substrate is made of an insulating material; the substrate has N×M grooves, and each M consecutive grooves form a test channel.

[0026] More preferably, the N×M grooves are arranged in a rectangular array of N rows and M columns, with each row being a test channel.

[0027] Preferably, the slots are disposed on two opposite sidewalls in the row direction within the groove.

[0028] Preferably, the grooves are independently shaped as either cubes or cuboids.

[0029] Secondly, the present invention provides a method for testing the performance of a catalytic electrode, employing the above-mentioned bipolar electrochemical test cell structure, comprising the following steps:

[0030] The first step involves assigning a test channel to each type of catalytic electrode to be tested. Within each test channel, a groove is used for testing. An electrolyte solution is added to the groove. One type of catalytic electrode to be tested is selected as the working electrode, and a metal electrode is selected as the counter electrode. The working electrode and the counter electrode are fixed on both sides of the groove to form an electrolysis chamber. The fixing method is that the two ends are inserted into two opposite slots. The working electrode clip and the sensitive electrode clip of the electrochemical workstation are connected to the catalytic electrode to be tested, and the reference electrode clip and the counter electrode clip are connected to the metal electrode. The LSV potential test range and scan speed are set to obtain the LSV curve of the catalytic electrode to be tested in one electrolysis chamber.

[0031] The second step involves assigning a test channel to each type of catalytic electrode to be tested. Within each test channel, two grooves are used for testing. An electrolyte solution is added to each groove, and one type of catalytic electrode to be tested is selected as the working electrode, while a metal electrode is selected as the counter electrode. The working and counter electrodes are fixed on opposite sides of the groove, with each end inserted into a corresponding slot. The catalytic electrode to be tested located at one end of all the test grooves is connected to both the working electrode clip and the sensitive electrode clip of the electrochemical workstation. The metal electrode located at the other end of all the test grooves is connected to both the reference electrode clip and the counter electrode clip of the electrochemical workstation. In adjacent test grooves, the metal electrode of one groove is electrically connected to the catalytic electrode to be tested in the other groove via conductive copper glue, forming two series-connected electrolytic chambers. The LSV potential test range and scan speed are set to obtain the LSV curves of the catalytic electrode to be tested within the two electrolytic chambers.

[0032] The third step is to follow the same procedure as the second step, and then use three to P grooves to perform tests to obtain the LSV curves of the catalytic electrode under test in three to P electrolysis chambers, where P≤M;

[0033] The fourth step is to plot the number of electrolysis chambers for various catalytic electrodes under test and the corresponding 10 mA / cm² values ​​in the LSV curves. 2 The linear relationship between current density and overpotential is calculated, and the linear slope is determined. By comparing the magnitude of the linear slope, the catalytic activity of each catalytic electrode under test is reflected (the smaller the linear slope, the better the catalytic activity of the catalytic electrode).

[0034] It should be noted that, in the above testing method, taking the first and second steps as examples, when the second step uses two grooves for testing, a groove can be added on the basis of the groove in the first step, or two grooves can be selected again for testing after cleaning. The third step is the same, and grooves can be added or the corresponding number of grooves can be selected after cleaning.

[0035] Preferably, the metal electrodes are independently nickel mesh, nickel sheet, or platinum sheet.

[0036] Preferably, the electrolyte solution is an alkaline electrolyte solution.

[0037] Preferably, in the first step, the range of the LSV potential test is 0V to -2V or 0 to 2V, and the scan speed is 5mV / s.

[0038] Preferably, in the second step, the range of the LSV potential test is 0V to -4V or 0 to 4V, and the scan speed is 5mV / s.

[0039] Preferably, in the third step, the range of the LSV potential test is 0V to -6V or 0 to 6V, and the scan speed is 5mV / s.

[0040] Thirdly, the present invention provides a method for continuously testing the voltage of a small chamber, employing the above-mentioned bipolar electrochemical test cell structure, comprising the following steps:

[0041] The first step involves assigning a test channel to each type of catalytic electrode to be tested. Within each test channel, a groove is used for testing. An electrolyte solution is added to the groove. One type of catalytic electrode to be tested is selected as the working electrode, and a metal electrode is selected as the counter electrode. The working electrode and the counter electrode are fixed on both sides of the groove to form an electrolysis chamber. The fixing method is that the two ends are inserted into two opposite slots. The working electrode clip and the sensitive electrode clip of the electrochemical workstation are connected to the catalytic electrode to be tested, and the reference electrode clip and the counter electrode clip are connected to the metal electrode. Under constant current, the ET curve of the catalytic electrode to be tested in one electrolysis chamber is tested.

[0042] The second step involves assigning a test channel to each type of catalytic electrode to be tested. Within each test channel, two grooves are used for testing. An electrolyte solution is added to each groove, and one type of catalytic electrode to be tested is selected as the working electrode, while a metal electrode is selected as the counter electrode. The working and counter electrodes are fixed on opposite sides of the groove, with each end inserted into a corresponding slot. The catalytic electrode to be tested located at one end of all the test grooves is connected to both the working electrode clip and the sensitive electrode clip of the electrochemical workstation. The metal electrode located at the other end of all the test grooves is connected to both the reference electrode clip and the counter electrode clip of the electrochemical workstation. In adjacent test grooves, the metal electrode of one groove is electrically connected to the catalytic electrode to be tested in the other groove via conductive copper glue, forming two series-connected electrolytic chambers. Under constant current, the ET curve of the catalytic electrode to be tested is measured within the two electrolytic chambers.

[0043] The third step is to follow the same procedure as the second step, and then use three to P grooves to perform tests to obtain the ET curves of the catalytic electrode under test in three to P electrolysis chambers, where P≤M;

[0044] The fourth step is to plot the linear relationship between the number of electrolysis chambers of various catalytic electrodes under test and the potential after the ET curve potential stabilizes under constant current, and calculate the slope corresponding to the linear relationship, i.e., the chamber voltage (under a certain constant current density, the external input voltage required for electrolysis is increased for each additional electrolysis chamber, and the slope is also the chamber voltage).

[0045] It should be noted that, in the above testing method, taking the first and second steps as examples, when the second step uses two grooves for testing, a groove can be added on the basis of the groove in the first step, or two grooves can be selected again for testing after cleaning. The third step is the same, and grooves can be added or the corresponding number of grooves can be selected after cleaning.

[0046] Preferably, the metal electrodes are independently nickel mesh, nickel sheet, or platinum sheet.

[0047] Preferably, the electrolyte solution is an alkaline electrolyte solution.

[0048] Preferably, in the first step, the constant current is 10mA~100mA, and the test time is 3600s.

[0049] Preferably, in the second step, the constant current is 10mA~100mA, and the test time is 3600s.

[0050] Preferably, in the third step, the constant current is 10mA~100mA, and the test time is 3600s.

[0051] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0052] 1. The bipolar electrochemical test cell structure of the present invention differs from the circular electrolytic cell in the prior art. It adopts a flat plate design with multiple test channels and multiple electrolytic chambers separated in the middle. It can realize the performance test of the catalytic electrode of the simulated bipolar electrolytic cell and can also be used for continuous testing of the chamber voltage.

[0053] 2. The bipolar electrochemical test cell structure and the method for testing the performance of catalytic electrodes of the present invention employ multiple electrolysis chambers connected in series, which can detect the performance of the same catalytic electrode under test in different numbers of electrolysis chambers, and employ multiple test channels connected in parallel, which can simultaneously measure the performance of multiple catalytic electrodes under test.

[0054] 3. The bipolar electrochemical test cell structure and the method for testing the performance of the catalytic electrode of the present invention simulate the working environment of the catalytic electrode in an electrolyzer under real working conditions. The test performance is not affected by the reference electrode and the counter electrode. The performance of the tested catalytic electrode can more closely reflect the performance of the catalytic electrode in actual electrolyzer operation.

[0055] 4. The bipolar electrochemical test cell structure and the method for testing the performance of catalytic electrodes of the present invention can achieve efficient and rapid screening of the electrochemical performance of catalytic electrodes, aiming to improve the convenience of characterizing and screening the performance of catalytic electrodes in electrolyzers. At the same time, it simulates the working state of catalytic electrodes in electrolyzers under actual working conditions, making the performance of the screened catalytic electrodes closer to the real working conditions.

[0056] 5. The bipolar electrochemical test cell structure and the method for testing the performance of catalytic electrodes of the present invention are applicable to all catalytic electrode performance tests, including but not limited to water electrolysis, hydrogen fuel cells and other fields.

[0057] 6. The bipolar electrochemical test cell structure and the method for continuously testing the cell voltage of the present invention can continuously test the change of external voltage after several electrolysis cells are stacked together, and plot the linear relationship between the number of cells and the corresponding voltage under a specific current density, and obtain the linear slope, providing data support and basis for the design of the number of cells and cell voltage of the electrolyzer (such as providing data support for the selection of catalytic electrodes, the design of the rated power of the electrolyzer, the adjustment of the load range, and the reduction of DC power consumption).

[0058] 7. The bipolar electrochemical test cell structure of the present invention and its method for testing the performance of catalytic electrodes and continuously testing the cell voltage do not require additional reference electrodes and counter electrodes, as well as complex data processing procedures, thus simplifying experimental testing conditions and data processing procedures. Attached Figure Description

[0059] Figure 1 The diagrams show existing three-electrode test cells, unipolar electrolytic cells, and bipolar electrolytic cells. In the diagrams, A is a schematic of an existing three-electrode test cell, B is a schematic of a unipolar electrolytic cell, and C is a schematic of a bipolar electrolytic cell.

[0060] Figure 2 The LSV curves of the catalytic electrode tested using a three-electrode system are shown. In A, the actual test data is given with the potential relative to the silver / silver chloride reference electrode, and in B, the data from A is processed with the potential relative to the standard hydrogen electrode.

[0061] Figure 3 This is a top view of the bipolar electrochemical test cell of Embodiment 1 of the present invention;

[0062] In the diagram, 1. base, 2. groove, 3. slot.

[0063] Figure 4 The distribution of test channels and electrolysis chambers in the bipolar electrochemical test cell of Embodiment 1 of the present invention.

[0064] Figure 5 This is a flowchart of the continuous testing of the LSV and ET curves of the catalytic electrode using a bipolar electrochemical test cell in Embodiment 1 of the present invention. From left to right, the steps are the first to the third step (only the connection relationship of electrode 1 in the first test channel is shown in the figure; the connection method of electrodes 2 to 4 in the second to fourth test channels is the same as that in the first test channel).

[0065] Figure 6 The LSV curves of electrodes 1-4 in the first electrolysis chamber in Embodiment 1 of the present invention are shown.

[0066] Figure 7 The LSV curves of electrodes 1-2 in the first, second, and third electrolysis chambers of Embodiment 1 of the present invention are shown, and the LSV curves are based on the 10 mA / cm value in the LSV curves.2 The linear relationship between the number of electrolytic cells and the overpotential at the corresponding current density is plotted; where A is the LSV curve and B is the linear relationship between the number of electrolytic cells and the overpotential.

[0067] Figure 8 In Embodiment 1 of the present invention, electrodes 1-2 are subjected to 50 mA / cm in the first electrolysis chamber, the second electrolysis chamber, and the third electrolysis chamber. 2 The linear relationship between the ET curves under constant current density and the number of electrolytic cells and the corresponding stable voltage of the ET curves is plotted. Among them, A is the ET curve of electrode 1, B is the linear relationship between the number of electrolytic cells of electrode 1 and the corresponding voltage, C is the ET curve of electrode 2, and D is the linear relationship between the number of electrolytic cells of electrode 2 and the corresponding voltage. Detailed Implementation

[0068] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to embodiments.

[0069] In the following embodiments, various processes and methods not described in detail are conventional methods known in the art. Unless otherwise specified, the materials, reagents, apparatus, instruments, equipment, etc., used in the following embodiments are commercially available.

[0070] In the examples and comparative examples, four types of catalytic electrodes were used, namely electrode 1, electrode 2, electrode 3 and electrode 4, with three of each type. The catalytic electrodes used were commercially available water electrolysis hydrogen production electrodes (electrode 1 was a Raney nickel electrode from Baoshilai New Material Technology (Suzhou) Co., Ltd., electrode 2 was a ceramic electrode from Hefei Yingrui High-Tech New Material Technology Co., Ltd., and electrodes 3 and 4 were thermally sprayed electrodes from Deqing Hengchuan New Material Technology Co., Ltd.).

[0071] Comparative Example 1

[0072] like Figure 1 As shown, a three-electrode system was adopted based on a circular electrolytic cell. The catalytic electrode under test served as the working electrode (WE), saturated calomel (or silver / silver chloride, mercury / mercuric oxide, etc.) served as the reference electrode (RE), and a platinum sheet (or carbon rod) electrode served as the counter electrode (CE). The LSV curves of electrodes 1, 2, 3, and 4 were measured respectively, and the test results are shown below. Figure 2 As shown in Figure A, the potential relative to the silver / silver chloride reference electrode is obtained. Data processing of A yields... Figure 2 In the middle B, the potential is relative to the standard hydrogen electrode.

[0073] Example 1

[0074] like Figure 3 As shown, the bipolar electrochemical test cell structure of the present invention includes a substrate 1, which is flat and made of polytetrafluoroethylene. The substrate 1 has 4×4 grooves 2, which are arranged in a rectangular array of 4 rows and 4 columns. Each row of grooves 2 serves as a test channel. The grooves 2 are all cuboids. The depth of the grooves 2 is not particularly limited, such as 1.2 cm. Several slots 3 are symmetrically opened on two opposite side walls of each groove 2. The slots 3 are set on the two side walls of the groove in the row direction.

[0075] In the column direction, from bottom to top, the test channels are: the first test channel, the second test channel, the third test channel, and the fourth test channel; in the row direction, from left to right, the electrolysis chambers are: the first electrolysis chamber (referred to as chamber 1), the second electrolysis chamber (referred to as chamber 2), the third electrolysis chamber (referred to as chamber 3), and the fourth electrolysis chamber (referred to as chamber 4), etc. Figure 4 As shown.

[0076] like Figure 5 As shown, the method for testing the performance of the catalytic electrode and continuously testing the chamber voltage of the present invention includes the following steps:

[0077] The first step involves assigning a test channel to each type of catalytic electrode to be tested (electrode 1 corresponds to the first test channel, electrode 2 to the second test channel, electrode 3 to the third test channel, and electrode 4 to the fourth test channel). In each test channel, an electrolyte solution is added to the first electrolysis chamber. One type of catalytic electrode to be tested and a nickel mesh electrode are fixed on both sides of the first electrolysis chamber by inserting a slot. The working electrode clip (green) and sensitive electrode clip (white) of the electrochemical workstation are connected to the catalytic electrode to be tested. The reference electrode clip (yellow) and counter electrode clip (red) are both connected to the nickel mesh electrode. The LSV potential test range and scan speed are set (the LSV potential test range is 0V to -2V, and the scan speed is 5mV / s). The LSV curve of the catalytic electrode to be tested in one electrolysis chamber is obtained. Under constant current (50mA), the ET curve of the catalytic electrode to be tested in one electrolysis chamber is detected.

[0078] By comparing the LSV curves of various catalytic electrodes under test in one electrolysis chamber, the catalytic performance of various catalytic electrodes under test in one electrolysis chamber is obtained;

[0079] The second step involves assigning a test channel to each type of catalytic electrode to be tested (corresponding as in the first step). In each test channel, an electrolyte solution is added to the first and second electrolysis chambers. A catalytic electrode to be tested and a nickel mesh electrode are fixed on the left and right sides of each electrolysis chamber, respectively, by inserting a slot. Within the same test channel, the nickel mesh electrode in the first electrolysis chamber is adjacent to the catalytic electrode to be tested in the second electrolysis chamber and is electrically connected by conductive copper glue, forming a dual electrode (the first and second electrolysis chambers are connected in series). The working electrode clip and sensitive electrode clip of the electrochemical workstation are connected to the catalytic electrode to be tested in the first electrolysis chamber, while the reference electrode clip and counter electrode clip are connected to the nickel mesh electrode in the second electrolysis chamber. The LSV potential test range and scan speed are set (the LSV potential test range is 0V to -4V, and the scan speed is 5mV / s). The LSV curve of the catalytic electrode to be tested in one electrolysis chamber is obtained, and the ET curve of the catalytic electrode to be tested in one electrolysis chamber is detected under constant current (50mA).

[0080] By comparing the LSV curves of various catalytic electrodes under test in two electrolysis chambers, the catalytic performance of various catalytic electrodes under test in two electrolysis chambers is obtained.

[0081] The third step involves assigning a test channel to each type of catalytic electrode to be tested (corresponding as in the first step). Within each test channel, electrolyte solution is added to the first, second, and third electrolysis chambers. A catalytic electrode to be tested and a nickel mesh electrode are fixed to the left and right sides of each electrolysis chamber, respectively, using an insertion slot. Within the same test channel, the nickel mesh electrode in the first electrolysis chamber is adjacent to the catalytic electrode to be tested in the second electrolysis chamber and is electrically connected via conductive copper adhesive, forming a dual-electrode configuration. The nickel mesh electrode in the second electrolysis chamber is adjacent to the catalytic electrode to be tested in the third electrolysis chamber and is electrically connected via conductive copper adhesive. The electrodes are connected to form a dual-electrode system (first, second, and third electrolysis chambers connected in series). The working electrode clip and sensitive electrode clip of the electrochemical workstation are connected to the independent catalytic electrode to be tested in the first electrolysis chamber. The reference electrode clip and counter electrode clip are both connected to the independent nickel mesh electrode in the third electrolysis chamber. The LSV potential test range and scan rate are set (LSV potential test range 0V~-6V, scan rate 5mV / s). The LSV curve of the catalytic electrode to be tested in one electrolysis chamber is obtained. Under constant current (50mA), the ET curve of the catalytic electrode to be tested in one electrolysis chamber is detected.

[0082] By comparing the LSV curves of various catalytic electrodes under test in the three electrolysis chambers, the catalytic performance of various catalytic electrodes under test in the three electrolysis chambers was obtained.

[0083] The fourth step involves plotting the number of electrolysis chambers for various catalytic electrodes under test and the corresponding LSV curves at 10 mA / cm². 2 The linear relationship between the corresponding overpotentials is calculated, and the linear slope is compared to reflect the catalytic activity of each catalytic electrode.

[0084] By plotting the linear relationship between the number of electrolysis chambers of various catalytic electrodes under test and the potential after the ET curve potential stabilizes under constant current, the slope corresponding to the linear relationship, i.e., the chamber voltage, is calculated.

[0085] Figure 6 The LSV curves for electrodes 1-4 in the first electrolysis chamber are shown. Compared to... Figure 2 The measured potential is relative to the standard hydrogen electrode, and the data does not require complex processing.

[0086] Figure 7 The LSV curves of electrodes 1-2 in the first, second, and third electrolysis chambers, respectively, and the LSV curves based on 10 mA / cm 2 The linear relationship between the number of electrolytic cells and the overpotential at the corresponding current density is plotted; where A is the LSV curve and B is the linear relationship between the number of electrolytic cells and the overpotential. Figure 7 From B, we can see that the slope of the linear relationship reflects the quality of the electrode performance; that is, the smaller the slope of electrode 1, the better its performance.

[0087] Figure 8 In Embodiment 1 of the present invention, electrodes 1-2 are subjected to 50 mA / cm in the first electrolysis chamber, the second electrolysis chamber, and the third electrolysis chamber. 2 The graphs show the linear relationship between the ET curves at constant current density and the stable voltage corresponding to the number of electrolytic cells. A represents the ET curve for electrode 1, B represents the linear relationship between the number of electrolytic cells for electrode 1 and the corresponding voltage, C represents the ET curve for electrode 2, and D represents the linear relationship between the number of electrolytic cells for electrode 2 and the corresponding voltage. The slope of the linear relationship indicates the amount of external voltage required for electrolysis with each additional electrolytic cell, i.e., the cell voltage. The cell voltage directly determines the DC power consumption of the electrolytic cell.

[0088] Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the embodiments. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for testing the performance of a catalytic electrode, characterized in that, The bipolar electrochemical test cell structure is used for testing. The bipolar electrochemical test cell structure includes N test channels. Each test channel includes M grooves arranged continuously. The walls of the grooves at the connection between two adjacent grooves are made of insulating material. Several slots are symmetrically opened on the two opposite side walls of each groove. N≥2, M≥3. The method for testing the performance of the catalytic electrode includes the following steps: The first step involves assigning a test channel to each type of catalytic electrode to be tested. Within each test channel, a groove is used for testing. An electrolyte solution is added to the groove. One type of catalytic electrode to be tested is selected as the working electrode, and a metal electrode is selected as the counter electrode. The working electrode and the counter electrode are fixed on both sides of the groove to form an electrolysis chamber. The fixing method is that the two ends are inserted into two opposite slots. The working electrode clip and the sensitive electrode clip of the electrochemical workstation are connected to the catalytic electrode to be tested, and the reference electrode clip and the counter electrode clip are connected to the metal electrode. The LSV potential test range and scan speed are set to obtain the LSV curve of the catalytic electrode to be tested in one electrolysis chamber. The second step involves assigning a test channel to each type of catalytic electrode to be tested. Within each test channel, two grooves are used for testing. An electrolyte solution is added to each groove, and one type of catalytic electrode to be tested is selected as the working electrode, while a metal electrode is selected as the counter electrode. The working and counter electrodes are fixed on opposite sides of the groove, with each end inserted into a corresponding slot. The catalytic electrode to be tested located at one end of all the test grooves is connected to both the working electrode clip and the sensitive electrode clip of the electrochemical workstation. The metal electrode located at the other end of all the test grooves is connected to both the reference electrode clip and the counter electrode clip of the electrochemical workstation. In adjacent test grooves, the metal electrode of one groove is electrically connected to the catalytic electrode to be tested in the other groove via conductive copper glue, forming two series-connected electrolytic chambers. The LSV potential test range and scan speed are set to obtain the LSV curves of the catalytic electrode to be tested within the two electrolytic chambers. The third step is to follow the same procedure as the second step, and then use three to P grooves to perform tests to obtain the LSV curves of the catalytic electrode under test in three to P electrolysis chambers, where P≤M; The fourth step is to plot the number of electrolysis chambers for various catalytic electrodes under test and the corresponding 10 mA / cm² values ​​in the LSV curves. 2 The linear relationship between current density and overpotential is calculated, and the linear slope is determined. By comparing the magnitude of the linear slope, the catalytic activity of each catalytic electrode under test can be reflected.

2. The method for testing the performance of a catalytic electrode according to claim 1, characterized in that, The bipolar electrochemical test cell structure has N test channels arranged continuously, and the groove wall at the connection between two adjacent test channels is made of insulating material.

3. The method for testing the performance of a catalytic electrode according to claim 1, characterized in that, The bipolar electrochemical test cell structure includes a substrate, and the substrate is made of an insulating material. The substrate has N×M grooves, with each M consecutive grooves forming a test channel.

4. The method for testing the performance of a catalytic electrode according to claim 3, characterized in that, The N×M grooves are arranged in a rectangular array of N rows and M columns, with each row being a test channel.

5. The method for testing the performance of a catalytic electrode according to claim 4, characterized in that, The slots are located on two opposite sidewalls in the groove along the row direction.

6. The method for testing the performance of a catalytic electrode according to any one of claims 1-5, characterized in that, It possesses one or more of the following characteristics: The metal electrodes are all nickel mesh, nickel sheet, or platinum sheet; In the first step, the LSV potential test range is 0V to -2V or 0 to 2V, and the scan speed is 5mV / s; In the second step, the LSV potential test range is 0V to -4V or 0 to 4V, and the scan speed is 5mV / s; In the third step, the LSV potential test range is 0V to -6V or 0 to 6V, and the scan speed is 5mV / s.

7. A method for continuously testing the voltage of a small cell, characterized in that, The test is conducted using a bipolar electrochemical test cell structure, which includes N test channels. Each test channel includes M consecutively arranged grooves. The walls of the grooves at the connection between two adjacent grooves are made of insulating material. Several slots are symmetrically opened on the two opposite side walls of each groove, where N≥2 and M≥3. The method for continuously testing the cell voltage includes the following steps: The first step involves assigning a test channel to each type of catalytic electrode to be tested. Within each test channel, a groove is used for testing. An electrolyte solution is added to the groove. One type of catalytic electrode to be tested is selected as the working electrode, and a metal electrode is selected as the counter electrode. The working electrode and the counter electrode are fixed on both sides of the groove to form an electrolysis chamber. The fixing method is that the two ends are inserted into two opposite slots. The working electrode clip and the sensitive electrode clip of the electrochemical workstation are connected to the catalytic electrode to be tested, and the reference electrode clip and the counter electrode clip are connected to the metal electrode. Under constant current, the ET curve of the catalytic electrode to be tested in one electrolysis chamber is tested. The second step involves assigning a test channel to each type of catalytic electrode to be tested. Within each test channel, two grooves are used for testing. An electrolyte solution is added to each groove, and one type of catalytic electrode to be tested is selected as the working electrode, while a metal electrode is selected as the counter electrode. The working and counter electrodes are fixed on opposite sides of the groove, with each end inserted into a corresponding slot. The catalytic electrode to be tested located at one end of all the test grooves is connected to both the working electrode clip and the sensitive electrode clip of the electrochemical workstation. The metal electrode located at the other end of all the test grooves is connected to both the reference electrode clip and the counter electrode clip of the electrochemical workstation. In adjacent test grooves, the metal electrode of one groove is electrically connected to the catalytic electrode to be tested in the other groove via conductive copper glue, forming two series-connected electrolytic chambers. Under constant current, the ET curve of the catalytic electrode to be tested is measured within the two electrolytic chambers. The third step is to follow the same procedure as the second step, and then use three to P grooves to perform tests to obtain the ET curves of the catalytic electrode under test in three to P electrolysis chambers, where P≤M; The fourth step is to plot the linear relationship between the number of electrolysis chambers of various catalytic electrodes under test and the potential after the ET curve potential stabilizes under constant current, and to calculate the slope of the linear relationship, i.e., the chamber voltage.

8. The method for continuously testing cell voltage according to claim 7, characterized in that, The bipolar electrochemical test cell structure has N test channels arranged continuously, and the groove wall at the connection between two adjacent test channels is made of insulating material.

9. The method for continuously testing cell voltage according to claim 7, characterized in that, The bipolar electrochemical test cell structure includes a substrate, and the substrate is made of an insulating material. The substrate has N×M grooves, with each M consecutive grooves forming a test channel.

10. The method for continuously testing cell voltage according to claim 9, characterized in that, The N×M grooves are arranged in a rectangular array of N rows and M columns, with each row being a test channel.

11. The method for continuously testing cell voltage according to claim 10, characterized in that, The slots are located on two opposite sidewalls in the groove along the row direction.

12. The method for continuously testing cell voltage according to any one of claims 7-11, characterized in that, It possesses one or more of the following characteristics: The metal electrodes are all nickel mesh, nickel sheet, or platinum sheet; In the first step, the constant current is 10mA~100mA, and the test time is 3600s; In the second step, the constant current is 10mA~100mA, and the test time is 3600s; In the third step, the constant current is 10mA~100mA, and the test time is 3600s.

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