CN203606313U - Work electrode for electrochemical testing of porous electrode material of flow cell - Google Patents

Abstract

The utility model relates to a work electrode for electrochemical testing of a porous electrode material of a flow cell. The work electrode comprises an electrode sleeve, a lead, a sealing gasket, an electrode and a porous electrode material jacket, wherein the lower part of the electrode sleeve can be connected with the upper part of the porous electrode material through a thread; the sealing gasket is arranged between the electrode sleeve and the porous electrode material jacket, and prevents a bath solution from permeating; a round or square hole is formed at the lower part of the porous electrode material jacket and used for placing of the porous electrode material. The work electrode is simple in structure, convenient to operate, low in cost, strong in practicability, and applicable to electrochemical measurement of porous materials such as a carbon felt, a graphite felt and the like.

Description

A working electrode for electrochemical testing of porous electrode materials for flow batteries

technical field

The utility model relates to the field of electrochemical performance testing of materials, in particular to a working electrode for electrochemical testing of electrode materials used in all-vanadium redox flow batteries.

Background technique

Due to its independent output power and capacity, the all-vanadium redox flow battery has flexible system design; high energy efficiency, long life, high operation stability and reliability, and low self-discharge; large degree of freedom in site selection, no pollution, and simple maintenance. With the advantages of low operating cost and high safety, it has broad development prospects in large-scale energy storage. It is considered to be an effective method to solve the random and intermittent unsteady characteristics of renewable energy power generation systems such as solar energy and wind energy. There are significant demands in power generation and smart grid construction.

As one of the key components of the flow battery, the performance of the electrode has a great influence on the flow battery, especially the electrocatalytic activity of the electrode, which directly determines the intrinsic reaction rate of the electrochemical reaction and greatly affects the performance of the battery. Operating current density and energy efficiency. Electrochemical testing using a three-electrode system is a common method for evaluating the electrocatalytic activity of electrode materials.

The current working electrode for electrochemical measurement is mainly composed of electrodes, electrode sleeves and wires. Usually, the electrode sleeve is made of insulating tubes such as polytetrafluoroethylene, and the electrode whose outer diameter is slightly larger than the inner diameter of the electrode sleeve is tightly pressed into the electrode sleeve. The electrodes and the ends of the wires can be connected by welding or bonding with conductive glue or adhesive. This kind of working electrode is more suitable for studying the chemical substances dissolved in the solution, or the electrochemical characteristics of a certain gas introduced from the outside. If it is used to evaluate the electrocatalytic performance of electrode materials, it is more suitable for testing powder materials, that is, powder materials and binders are made into ink through solvents, and then dropped on the surface of the working electrode, and tested after drying. However, the electrode materials of current flow batteries are mainly porous carbon fiber braided materials such as carbon felt or graphite felt. If the above working electrode is used, it needs to be ground into powder, but the grinding process will cause damage to the carbon fiber, resulting in Both the microstructure and the specific surface area changed dramatically, making the test results inaccurate. Therefore, most of the current electrochemical tests of electrode materials for flow batteries are performed by embedding electrode samples with resin or paraffin and then polishing to expose the electrode surface. In this way, on the one hand, the electrode manufacturing process is complicated and time-consuming; on the other hand, the grinding process may damage the carbon fiber surface, resulting in deviations in experimental data and affecting the accuracy of measurement results.

Utility model content

The problem to be solved by the utility model is to provide a working electrode for electrochemical measurement with simple structure, convenient operation and strong practicability, especially suitable for electrochemical measurement of porous materials such as carbon felt and graphite felt.

In order to solve the above problems, the utility model adopts the following technical solutions:

A working electrode for electrochemical testing of a porous electrode material for a flow battery, comprising an electrode sleeve, a sealing gasket, an electrode, and a jacket for a porous electrode material, the lower end of the electrode sleeve is provided with a groove, and the electrode is placed in the groove of the electrode sleeve The upper end of the porous electrode material jacket is provided with a groove, and the bottom of the groove is provided with a through hole downward, and the lower end of the electrode sleeve is placed in the groove at the upper end of the porous electrode material jacket; the lower end surface of the electrode sleeve and the porous electrode material clamp There is a sealing gasket between the bottom of the groove of the sleeve, and a small hole is opened on the sealing gasket under the electrode. The position of the small hole corresponds to the through hole at the bottom of the groove; the electrode communicates with the through hole at the bottom of the groove through the small hole. The other side is led out with a wire.

The lower part of the electrode sleeve is provided with external threads, and the inner wall of the groove at the upper end of the porous electrode material jacket is provided with internal threads, and the electrode sleeve and the porous electrode material jacket are screwed together through threads.

The sealing gasket is placed between the electrode sleeve and the porous electrode material jacket to prevent the electrolyte from infiltrating; the bottom of the groove of the porous electrode material jacket has a circular or square through hole for placing the porous electrode to be tested Material.

The sum of the height of the through hole and the thickness of the sealing gasket is equal to the thickness of the sample to be tested; the electrode material is glassy carbon or metal titanium with weak catalytic activity for the redox reaction of vanadium ions to obtain a low background current.

The electrode cover and the porous electrode material jacket are made of polytetrafluoroethylene or polyether ether ketone.

The sealing gasket is a fluorine rubber or polytetrafluoroethylene gasket.

The sample placement hole in the porous electrode material jacket can be designed and processed according to the shape and size of the sample to be tested, but should be smaller than the size of the electrode to ensure complete contact between the sample to be tested and the electrode.

The utility model is mainly used for performing electrochemical tests on porous electrode materials, for example, researching the electrocatalytic performance of the electrode materials of all-vanadium redox flow batteries. The invention has the advantages of simple structure, convenient operation, low cost and strong practicability; it does not damage the porous electrode material, is very beneficial to the research on the electrochemical performance of the electrode material of the all-vanadium redox flow battery, and screens the electrode material at the initial stage of battery design.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the working electrode of the present invention.

Among them: 1 lead wire; 2 electrode cover; 3 electrode; 4 sealing gasket; 5 porous electrode material jacket; 6 porous material sample to be tested.

Detailed ways

Example

Below in conjunction with Fig. 1, the utility model is further explained by specific embodiments.

As shown in Figure 1, a working electrode for electrochemical testing of a porous electrode material for a flow battery includes 1 wire, 2 electrode sleeves, 3 electrodes, 4 sealing gaskets and 5 porous electrode material jackets, wherein the wire 1 can be Copper, silver, gold, platinum and other metal wires or metal rods; the electrode 3 is a disc made of glassy carbon or metal titanium, with a height of 2-5mm and a diameter of 3-10mm; Press into the electrode sleeve 2; the electrode sleeve 2 and the porous electrode material jacket 5 are made of polytetrafluoroethylene, the inner diameter of the electrode sleeve is 3-10mm, the outer diameter is 6-20mm, and the outer diameter of the porous electrode material jacket 5 is 16- 30mm, the inner diameter of the upper part is 6-20mm, which is connected with the electrode sleeve 2 through threads, the inner diameter of the lower part is 3-6mm, and the height is 2-5mm, which is used to place the porous material sample to be tested. The sealing gasket 4 is a fluorine rubber sheet with a thickness of 0.5-1mm, which is placed between the electrode sleeve and the porous electrode material jacket to prevent the electrolyte from penetrating.

When carrying out electrochemical testing, it is only necessary to press the cut porous material sample into the small hole at the lower part of the porous electrode material jacket 5 and press it tightly so that it is in good contact with the electrode 3, and then the measurement can be started. It is simple and quick to replace the sample, just take out the porous material sample that has been measured in the small hole, and then press in a new sample. If the surface of the electrode 3 is polluted, the porous electrode material jacket 5 connected by thread can be removed, and then the surface of the electrode 3 can be polished and cleaned, which is easy to operate and easy to use. And according to the size of the sample to be tested, different porous electrode material jackets can be replaced to achieve the purpose of "one pole with multiple functions".

Claims (8)

1. A working electrode for electrochemical testing of porous electrode materials for flow batteries, including electrode sleeves (2), sealing gaskets (4), electrodes (3), and porous electrode material jackets (5), characterized in that: The lower end of the electrode cover (2) is provided with a groove, and the electrode (3) is placed in the groove of the electrode cover; the upper end of the porous electrode material jacket (5) is provided with a groove, and the bottom of the groove is provided with a through hole downward, and the electrode The lower end of the sleeve (2) is placed in the groove at the upper end of the porous electrode material jacket (5); a sealing gasket is provided between the lower end surface of the electrode sleeve (2) and the bottom of the groove of the porous electrode material jacket (5) (4), there is a small hole on the sealing gasket (4) below the electrode (3), the position of the small hole corresponds to the through hole at the bottom of the groove; the electrode (3) communicates with the through hole at the bottom of the groove through the small hole . 2. The working electrode according to claim 1, characterized in that the electrode (3) is led out through the wire (1). 3. The working electrode according to claim 1, characterized in that: the lower part of the electrode sleeve (2) is provided with external threads, the inner wall of the groove at the upper end of the porous electrode material jacket (5) is provided with internal threads, and the electrode sleeve (2) It is screwed with the porous electrode material jacket through threads. 4. The working electrode according to claim 1, characterized in that: the sealing gasket is placed between the electrode sleeve and the porous electrode material jacket to prevent the electrolyte from penetrating; the bottom of the groove of the porous electrode material jacket is open There are round or square through holes for placing the porous electrode material to be tested. 5. According to the described working electrode of claim 1, it is characterized in that: the sum of the height of the through hole and the thickness of the sealing gasket is equal to the thickness of the sample to be measured; carbon or titanium metal for low background currents. 6. The working electrode according to claim 1, characterized in that: the electrode cover and the porous electrode material jacket are made of polytetrafluoroethylene or polyether ether ketone. 7. The working electrode according to claim 1, characterized in that: the sealing gasket is a fluorine rubber or polytetrafluoroethylene gasket. 8. The working electrode according to claim 1, characterized in that: the sample placement hole in the porous electrode material jacket can be designed and processed according to the shape and size of the sample to be tested, but should be smaller than the size of the electrode to ensure The test sample is in full contact with the electrode.

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