CN111430743B

CN111430743B - Vanadium cell electrolyte reduction device

Info

Publication number: CN111430743B
Application number: CN202010247731.1A
Authority: CN
Inventors: 刘帅舟; 史小虎
Original assignee: Hunan Fangu New Energy Technology Co ltd
Current assignee: Hunan Fangu New Energy Technology Co ltd
Priority date: 2020-03-31
Filing date: 2020-03-31
Publication date: 2021-06-01
Anticipated expiration: 2040-03-31
Also published as: CN111430743A

Abstract

The invention provides a vanadium battery electrolyte reduction device, which is a tubular electrolytic cell and mainly comprises an anode tube body (2), a cathode tube body (1) and a middle diaphragm (3), and is characterized in that the cathode tube body is open and comprises a frame and a cathode plate (6) arranged on the frame, the anode tube body (2) is closed, so that electrolyte in an anode is isolated in the anode tube body, and the reduction device is also provided with a support (7) for allowing the reduction device to be stably placed in a liquid filling port of a liquid storage tank of a vanadium battery system. Compared with the vanadium battery electrolyte reduction device in the prior art, the vanadium battery electrolyte reduction device is light and convenient.

Description

Vanadium cell electrolyte reduction device

Technical Field

The invention relates to the field of devices of renewable energy sources, in particular to a device for a flow battery, and more particularly to a recovery device of vanadium electrolyte.

Background

The vanadium battery has a series of advantages of high power, large capacity, high efficiency, long service life, environmental protection and the like, and has good application prospects in the fields of wind-solar power generation, power grid peak regulation, uninterrupted power supply, emergency power supply and the like.

The vanadium redox battery generally uses 3.5-valent (V (iii)/V (iv) ═ 1: 1) electrolyte as initial electrolyte, and injects the initial electrolyte into the positive and negative electrolyte tanks respectively according to equal volume, and the electrolyte is respectively conveyed from the tanks to the positive and negative electrodes of the pile by a pump to carry out electrochemical reaction, and then returns to the electrolyte tank to continuously circulate, so as to complete charging and discharging. After multiple charge-discharge cycles, due to side reactions such as vanadium ion transmembrane migration, hydrogen evolution and oxygen evolution, and due to oxidation of the cathode electrolyte caused by poor system airtightness, mismatching of ion valence states of the anode electrolyte and the cathode electrolyte occurs, so that the capacity of the battery is attenuated, the performance of the battery is influenced, and the service life of the battery is shortened. The capacity of the battery can be restored by adjusting the average valence of the vanadium ions in the positive electrolyte and the negative electrolyte.

Common methods for adjusting the ionic valence state to recover the battery capacity include a chemical reduction method and an electrolytic reduction method. The chemical reduction method is to add a certain amount of reducing agent into the positive electrode electrolyte; the electrolytic reduction method is to carry out electrolytic reduction on the positive electrolyte of the vanadium cell by an external electrolytic device.

Chinese patent application publication CN 103035963 a discloses a method for in-situ recovery of battery capacity, which uses organic, inorganic or their composite reducing agent to perform valence reduction on the positive electrolyte, and has simple process, easily available raw materials, and no need of external equipment. However, the method needs to be carried out under the conditions of battery charging and discharging and anode electrolyte circulating flow, and a large amount of gas is generated when an organic reducing agent is adopted, so that the method is easy to threaten a galvanic pile and even the whole vanadium battery system; the amount of the reducing agent is difficult to be precise, and impurities are easy to be introduced. Chinese patent publication CN 204257760U discloses a mobile high-power all-vanadium redox flow battery electrolyte online recovery device, wherein an electrolysis device and a pipeline conveying system are integrated in a mobile box body, the vanadium electrolyte can be recovered online on site, the transfer process of the electrolyte is omitted, the operation is simple, but the device needs more integrated pipelines, pumps and valves, has high energy consumption, is easy to remain the vanadium electrolyte, and causes cross pollution to different vanadium batteries; the integrated box body has larger volume and weight, and is not beneficial to being transported to the site of the vanadium battery system.

Disclosure of Invention

The invention aims to lighten and facilitate the vanadium battery electrolyte reduction device in the prior art.

The invention provides a vanadium battery electrolyte reduction device which is a tubular electrolytic cell and mainly comprises an anode tube body, a cathode tube body and a middle partition film. The cathode tube body is open and comprises a frame and a cathode plate installed on the frame, the anode tube body is closed, so that electrolyte in an anode is isolated in the anode tube body, and the reduction device is further provided with a support piece which allows the reduction device to be stably placed in a liquid injection port of a liquid storage tank of the vanadium battery system.

In one embodiment, the supporting members are lugs or hooks symmetrically arranged on the upper parts of the cathode tube body and the anode tube body, so that the reduction device is allowed to be hung in a liquid inlet of a liquid storage tank of the vanadium battery system.

In one embodiment, the frame includes an upper plate, a lower plate, a cathode frame for securing an intermediate membrane, and a backbone connected between the upper and lower plates and fixedly connected to the cathode frame.

In one embodiment, the cathode plates of the reduction apparatus are installed in the slots of the upper and lower plate members.

In one embodiment, the tabs of the cathode and anode plates of the reduction apparatus are located at the upper ends of the anode and cathode tubes.

In one embodiment, the anode tube has an exhaust port at an upper end thereof.

In one embodiment, the upper end of the anode tube body is provided with a liquid inlet.

In one embodiment, the anode tube has a drain port at a bottom thereof.

The device of the present invention fundamentally changes the operation mode in the prior art. The vanadium electrolyte electrolytic reduction device of the invention omits a pipeline conveying system and a liquid storage tank in the conventional electrolytic device, and has low cost and low energy consumption; the electrolytic reduction can be directly carried out in the electrolyte storage tank, the step of transferring the electrolyte is avoided, the cleaning is easy, and the introduction of impurities can be effectively avoided; the device has simple structure, is convenient to transport to the vanadium cell system site, and saves the transportation cost of the electrolyte returning to the factory for reduction treatment.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic view of an embodiment of a vanadium electrolyte reduction apparatus according to the present invention.

In the figure: 1-cathode tube body, 2-anode tube body, 3-intermediate diaphragm, 4-anode plate tab, 5-cathode plate tab, 6-cathode plate, 7-supporting piece, 8-exhaust port, 9-liquid inlet, 10-lower plate and 13-framework.

Detailed Description

The present invention will be further described with reference to the following detailed description, wherein the drawings are provided for illustrative purposes only and are not intended to be limiting; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

As shown in fig. 1, in an embodiment, the vanadium redox battery electrolyte reduction device is a tubular electrolytic cell, and mainly comprises an anode tube body 2, a cathode tube body 1 and a middle diaphragm 3, wherein the middle diaphragm 3 is clamped between two plate frames, a plurality of screw holes are formed in the peripheries of the plate frames, and the cathode tube body and the anode tube body are fixed together through bolts. The cathode tube 1 is open and mainly comprises a tube frame and a cathode plate 6 mounted on the frame. The tube frame comprises an upper plate (not shown), a lower plate 10, the cathode compartment frame can be considered as a part of the tube frame, and the frame further comprises a frame 13 connected between the upper and lower plates and fixedly connected to the cathode compartment frame. The anode tube body is closed, so that electrolyte in the anode is isolated in the anode tube body, and the reduction device is also provided with a support member 7, so that the reduction device is allowed to be stably placed in a liquid injection port of a liquid storage tank of the vanadium battery system.

In the practice of the invention, the cross-sectional dimensions of the reduction apparatus are selected so that it can be placed in a vanadium battery reservoir. When the reduction unit is operated, the plates of the cathode (the perforated plates shown in fig. 1) are exposed to the vanadium battery reservoir so that the entire reservoir becomes the cathode of the electrolytic cell. The anode chamber formed by the anode tube body is closed, and the vanadium electrolyte in the liquid storage tank can be reduced by connecting an external circuit to the two tabs 5 and 4, so that high-valence vanadium ions are reduced to lower valence.

The reduction end point can be controlled by two methods of time setting or real-time potential detection. The former calculates the electric quantity to be applied according to the volume and the concentration of the vanadium electrolyte to be processed and the valence of the vanadium ions, so as to obtain the time required for electrolysis, and the electrolysis is automatically stopped after the preset time is reached. The latter is to monitor the potential of vanadium ion in real time by a potential detection device, and automatically stop electrolytic reduction after reaching a preset value.

In this embodiment, the support members are lugs or hooks symmetrically disposed on the upper portions of the cathode tube and the anode tube, allowing the reduction device to be hung at a liquid injection port of a liquid storage tank of the vanadium battery system, so that the cathode plate 6 is immersed in the electrolyte of the liquid storage tank. It will be readily appreciated that other shapes or configurations of the auxiliary device are possible, as long as the fluid reservoir of the reducing device can be easily removed after the reduction is completed.

As shown in FIG. 1, the cathode plate 6 of the reduction apparatus is fixedly installed by the upper and lower plate members of the anode tube body 1, and a groove is provided in the lower plate member 10, in which the cathode plate is seated. The upper plate is provided with a via hole through which the tab 5 is fixed.

The anode tube body 2 forms a closed anode reaction area, and dilute sulfuric acid is used as an anolyte. The top of the anode tube body 2 is provided with a liquid inlet 9 for supplementing dilute sulfuric acid solution. An air outlet 8 is also arranged for discharging oxygen generated by the electrolytic reaction, and a liquid outlet 7 is arranged at the bottom for replacing the anolyte. In the working state, the liquid inlet and the liquid outlet are in a normally closed state and are controlled by a valve.

Other aspects of the reduction apparatus of the present invention may employ techniques known in the art of electrolytic cells, such as selection of materials for the components, fastening of the components, and the like.

The embodiment of the invention can understand that the electrolytic reduction device can be directly inserted into the vanadium battery system electrolyte storage tank from the electrolyte injection port, is fixed on the electrolyte storage tank through the supporting piece, directly carries out electrolytic reduction on the vanadium electrolyte, omits the transfer step of treating the electrolyte, is easy to clean, and can effectively avoid introducing impurities. The device omits a pipeline conveying system and a liquid storage tank in the conventional electrolysis device, and has low cost and low energy consumption. The device has simple structure, is convenient to transport to the vanadium cell system site, and saves the transportation cost of the electrolyte returning to the factory for reduction treatment.

Claims

1. The utility model provides a vanadium cell electrolyte reduction device, it is a cast electrolytic cell, mainly comprises anode tube body (2), cathode tube body (1) and intermediate barrier (3), its characterized in that, the cathode tube body is open, including frame and negative plate (6) of installing on this frame, anode tube body (2) are closed for electrolyte in the positive pole is kept apart in the anode tube body, reduction device still has support piece (7), allows reduction device firmly to be placed in the mouth of annotating the liquid of vanadium cell system liquid storage pot.

2. The vanadium redox battery electrolyte solution reduction device according to claim 1, wherein the supporting members are lugs or hooks symmetrically arranged on the upper parts of the cathode tube body and the anode tube body, so as to allow the reduction device to be hung in a liquid inlet of a vanadium redox battery system liquid storage tank.

3. The vanadium battery electrolyte reduction device according to claim 1, wherein the frame comprises an upper plate, a lower plate (10), a cathode plate frame for fixing an intermediate diaphragm, and a skeleton (13) connected between the upper plate and the lower plate and fixedly connected to the cathode plate frame.

4. A vanadium battery electrolyte reduction device according to claim 3, characterized in that the cathode plates (6) of the reduction device are mounted in the slots of the upper and lower plates.

5. The vanadium battery electrolyte reduction device according to claim 1, wherein the tabs (4, 5) of the cathode and anode plates of the reduction device are located at the upper ends of the anode and cathode tube bodies.

6. The vanadium redox battery electrolyte solution reducing device according to claim 1, wherein the anode tube body is provided at an upper end thereof with an exhaust port (8).

7. The vanadium redox battery electrolyte solution device according to claim 1, wherein the anode tube body is provided at an upper end thereof with a liquid inlet (9).

8. The vanadium redox battery electrolyte solution device of claim 1, wherein a drain port is formed at the bottom of the anode tube.