RU2775641C1 - Functional layout for studying the structure and demonstrating the operation of a flow redox battery - Google Patents

Abstract

FIELD: electrochemistry.

SUBSTANCE: claimed invention relates to educational and research equipment in the field of alternative energy and electrochemistry and can be used as a material base for conducting full-scale tests of flow redox batteries in research centers (institutions), or an educational and methodological object during workshops and laboratory work in educational institutions as part of the study of electrochemistry, courses of general chemistry, physics, physical chemistry, distributed energy and related disciplines. The claimed device is a prototype of a real object that appeared not so long ago in the world of practical application: a flow redox battery. It has an industrial appearance, which corresponds to its purpose: to show the true structure of the FRBs, their appearance and to enable the researcher/trainee/student to perform various manipulations aimed at controlling the processes taking place, studying them and, most importantly, understanding them as they are. A functional layout for studying the structure and demonstrating the operation of a flow redox battery includes a flow redox battery (stack), which is attached to a mounting plate with electrolyte tanks. The mounting plate, in turn, consists of two electrolyte tanks, which are fixed between a Teflon plate, in which there is a system of channels for the flow of electrolyte from the tank to the stack and back to the tank, two fluorine-rubber gaskets that give tightness and chemical resistance, and two duralumin plates that give rigidity and tightness to the mounting plate described above. All the indicated components of the mounting plate have through holes for being strapped together. On the lower part of this plate, in the middle, between the tanks, a pumping module is attached, designed to circulate electrolytes from both tanks through the stack.

EFFECT: possibility of visually studying the specifics of such a type of chemical current sources (CCS) as flow redox batteries (FRB), which makes it possible to test FRBs of various power and energy intensity, overall dimensions; the device involves the use of electrolytes of various composition, has a hoseless connection of the main functional units and the possibility of autonomous operation in the form of a chemical current source.

9 cl, 4 dwg

Description

Technical field

The claimed invention relates to teaching and research equipment in the field of alternative energy and electrochemistry and can be used as a material base for field tests of redox flow batteries in research centers (institutions), or as an educational and methodological object during workshops and laboratory works in educational institutions as part of the study of electrochemistry, courses in general chemistry, physics, physical chemistry, while getting acquainted with the principles of distributed energy and related disciplines. The present invention provides a wide range of opportunities for visual study of the specifics of this type of chemical power sources (CPS) as redox flow batteries (PRBs), allows testing of PRBs of various power and dimensions using electrolytes of various compositions, has a hose-free connection of the main functional units and the possibility of autonomous operation in the form of a chemical current source; acquaints the user with the appearance of energy storage devices of this type.

To obtain wind energy, windmills were invented, the blades of which, having an increasingly sophisticated shape, rotate under the influence of wind force. To get energy from waterfalls, hydroturbines were invented, the operating force of which is the resistance to the flow of water. In other cases, such resistance is created artificially by the construction of a dam. To get the energy of sunlight, solar panels were invented. In addition to these most common types of alternative energy sources, there are many others, but a special approach to the method of obtaining energy requires a special approach to the method of its accumulation and storage. Receiving energy from renewable sources - wind, water, sunlight, etc., is not a trivial task at all, because the sun shines only during the day; the strength of the wind depends on the degree and intensity of mixing and movement of air, on the intensity of temperature changes, etc .; mountain rivers are always more full-flowing in winter, and it is not possible to build dams on each of them, either for geological or other reasons. The conclusion from these words is clear - any form of alternative energy has a certain percentage of volatility in its volumes or possibilities for generation (the sun shines only during the day, etc.). To convert such forms of energy into electrical energy, redox flow batteries were created. This type of HIT has the ability to independently scale the energy reserve, by changing the volume of the tanks for the electrolyte, and power, by changing the overall dimensions of the stack (charge-discharge module). In addition, this type of HIT has the ability to quickly respond to fluctuations in the volume of energy coming to conversion, as well as the amount of energy already stored in the form of electricity required for release.

At the moment, the public is just beginning to gain knowledge in the field of alternative energy, reasonable consumption of natural resources, the need to save them, etc. A particularly important task is to reliably and easily tell about the ways of accumulating energy from alternative sources, about the processes underlying these methods and approaches. But, taking into account the degree and speed of technology development, as well as the novelty of the idea itself - a flow battery, it is necessary to have an object / equipment / stand - a functional layout that imitates this type of HIT. A visual aid attracts more attention, captivates and gives a characteristic duration of the student's interest in the subject of study. The claimed invention makes it possible to show the operation of a real object that imitates such a type of HIT as a PRB, as well as work with it independently, obtaining a complete picture for a true understanding of the battery structure and the principle of its operation. Thus, an urgent task is to create an installation for full-scale study of the principle of operation of redox flow batteries, their structure, main functional units, without which its operation is impossible; the implementation of this installation without the use of hose connections provides additional safety for the user, and the possibility of self-attaching the battery (stack) to the mounting plate with the pump module provides interactivity and involvement in the learning process. In addition, the proposed device has the ability to work autonomously as a chemical current source in the absence of any additional devices for storing a reserve amount of energy.

State of the art

An urgent task is to create a functional layout for studying the structure and demonstrating the operation of a redox flow battery that is integrated into the learning environment and at the same time not without the level of research equipment designed to study the structure and composition of a complex of redox flow batteries, testing this type of CPS with different the level of existing knowledge in the field of distributed energy (schoolchild / student / employee of a scientific organization). The designated device should be able to assemble various functional units together, while acquiring greater interest from the student; testing of PRBs of various power, energy intensity and overall dimensions; have a hose-free connection of the main functional units and the possibility of autonomous operation in the form of a chemical current source.

The closest and only closest to the claimed solution is a device for studying a vanadium redox battery [RU 2710683 C9, 2019], including a housing in which a power supply, a control board and a redox battery are located, as well as two electrolyte reservoirs, a means for displaying information , a block for changing the type of connection, a block of pumps and a compressor. The number of pairs of connectors in the block for changing the connection type corresponds to the number of membrane electrode blocks (MEAs) in the battery. The outlets of each of the reservoirs are connected in series with the corresponding pump and further with the corresponding inlets to the membrane-electrode block of the battery, and the outlets from the MEA are connected by tubes to the inlet of the corresponding reservoir. The compressor is connected by tubes in series with each of the tanks to form a closed circuit. The control board is electrically connected to the block for changing the type of connection, the information display device, the pump block, the compressor, the power supply unit and the battery. The disadvantage of this device is the presence of a large number of hose connections and tubes, which are places of increased risk for leakage and electrolyte outflow. In addition, the presented solution deprives the user of the opportunity to see the real appearance of redox flow batteries, and does not allow him to independently manipulate the assembly of the components together. Also, the described device does not have the ability to work autonomously, being, at the same time, a chemical current source. The implemented appearance and the initially assembled design makes it impossible for the user to participate in the assembly of the device; based on the structure, it is impossible to visually understand the principle of operation of real industrial PRBs, since all communications are hidden inside the case; there is no connection between the volumes of the electrolyte used, and, as a result, the exclusivity of the use as stationary energy storage devices with an industrial appearance.

Essence disclosure

The technical problem of the claimed invention is the creation of a functional layout designed to study the complex of redox flow batteries; consisting of separate functional units capable of being assembled into a single integral structure and providing the possibility of testing PRB (stack) of various overall dimensions, power and energy intensity, as well as operation on various electrolyte compositions; the connections of the main functional units must be made without the use of hoses, which will provide additional safety when working with the layout, and exclude the possibility of leakage. Upon reaching the maximum degree of battery charge, the layout must be able to work autonomously and simultaneously act as a source of energy. The design should ensure the assembly of its components, which will give additional interest to the user to participate in the process of studying such a type of CPS as PRB and make them more fully understand the principle of their operation. The size of the layout, the types of structural materials used should make it clear that this type of HIT is used exclusively as stationary energy storage devices. The proportionality of the volume of electrolyte used and the size of the stack should give an understanding of the size of real systems.

The technical result achieved by the claimed invention is the creation of a functional layout for studying the structure and demonstrating the operation of redox flow batteries, consisting of such functional units as:

1) a stack (charging/discharging module) made of chemically stable materials, which make it possible to work on various electrolyte systems;

2) a free-standing mounting plate with electrolyte reservoirs with a working volume of 1.5 liters and made to provide high chemical resistance to reagents used in most known electrolytes;

3) a pumping module, initially attached to the mounting plate by means of a tie, providing the flow of electrolyte of varying intensity through the stack.

Initially, the stack is located separately from the mounting plate and pump module assembled together, which allows the user to manipulate the stack to the plate itself (by means of a tie) using fluororubber gaskets. At the end of the battery charging process, the claimed device can act as an energy source, providing energy, at the same time, to itself and the consumer. The layout needs about 18 watts at peak consumption to be self-sufficient. The rest of the power can be taken by a consumer with an operating voltage of 12 V and a current of approximately 0.5-1.0 A. The time of stable operation of the consumer will vary depending on its mode of operation (requirements).

The technical result is achieved as follows. The stack has four elongated studs, with which it is attached to the mounting plate with electrolyte reservoirs through 4 through holes located in it. The fastening of these two functional units of the claimed invention is carried out by means of their ties to each other with 8 nuts. There are special recesses in the mounting plate, to which channels with circulating electrolyte fit inside the plate itself. First, gaskets are laid, which act as a seal for the pressure joint. Then a stack is installed on them and pressed with 4 nuts from the bottom of the plate. After a slight pressure, the system is checked for leaks by running a flow of distilled water through the entire layout, which was initially filled into the tanks. As soon as the water stops seeping from under the place where the stack is pressed against the mounting plate, the stack is pressed with 4 more nuts on top of the plate to level the bending of the plate and compensate for the pressure. This method of attaching the stack to the developed mounting plate makes it possible to mount a battery of various sizes, which makes it possible to test and study PRBs of various power, which is determined by the size of the electrode area of each MEA included in the stack. The energy intensity is determined by the volume of the electrolyte being poured and the concentration of the electroactive substance. Thus, the possibility of varying the energy reserve (energy intensity) of the layout is realized. The user can fill in a different volume of the prepared electrolyte according to his own method, which will vary the duration of the charge-discharge cycle. The concentration of the electroactive substance in the prepared electrolyte makes it possible to change the amount of energy received per unit of time and various other characteristics. All components of the mock-up that are in contact with the electrolyte are made of highly chemically stable materials (Teflon, fluoroelastomer, polyetheretherketone, etc.), which makes it possible to work with chemical reagents that are part of electrolytes with different aggressiveness. Both the stack and the pump module are clamped to the mounting plate with electrolyte reservoirs using clamping force via studs and nuts. A fully charged battery has an operating voltage range of 8-16 V and is capable of withstanding currents up to 2 A. Thus, the stored power, starting from the state of a fully charged battery, is enough to maintain the operation of the layout itself (ensuring the operation of the pump module - 18 W) and the consumer with parameters of 12 V and about 0.5-1.0 A, while acting as a chemical current source. When designing the proposed device, popular and familiar structural materials in the field of science and technology were used without any processing or packaging in a case. This measure is intended to improve the user's visual understanding of the structure and components of the PSR. The model has small overall dimensions of 280*145*375 mm, which makes it possible to quickly move it and use it in any necessary and convenient place, properly equipped for work of this nature. In addition, the implementation in such overall dimensions and weight of 4.95 kg tells how it will be in reality if the requirements for power indicators and energy reserve are proportionally increased. The mounting plate is made of a rectangular shape, which helps to conveniently place the electrolyte tanks on the sides in its lower part, and in the middle the pump module, located strictly opposite the stack. This arrangement of functional nodes makes the layout as compact and convenient as possible to use.

The design of the invention may be subject to various changes and modifications, understandable to a person skilled in the art based on reading the present description. Such changes do not limit the scope of the claims and are listed later in the text.

The device can be made in various forms. So, for example, a stack can have a rectangular shape, since most industrial stacks have just such a shape due to the specifics of the processes occurring on the surface of the electrodes during the conversion of chemical energy into electrical energy. In addition, the stack may be round in shape.

The top and bottom of the mounting plate can be made of titanium, which will increase the chemical resistance of the surface, but also the weight of the device itself. Fluororubber, used as a sealing and insulating material from chemically aggressive electrolyte reagents, can be replaced with perfluororubber or ethylene-propylene rubber, which will maintain or even increase chemical resistance, but increase the cost of the device. Teflon can be replaced with ebonite or other similar material. The mounting plate with electrolyte tanks can be made in a square shape. Tanks, in this case, can be cylindrical or square.

The pump in the pump module may include not a double-head diaphragm pump, but two single-head diaphragm pumps; also gear, centrifugal or any other type of pump can also be used as a pumping device. Such a replacement will entail serious changes in the design of the mounting plate itself, the method of mounting the pump, etc., but leaves room for it.

A stack can contain a different number of membrane-electrode blocks, starting from 2. At the same time, the layout allows testing single cells, the so-called membrane-electrode blocks. The stack and the MEA can have a completely different shape (rectangular, cylindrical, square, as it is made in the claimed device or otherwise), provided that the poles intended for fastening to the mounting plate are of the same size and located at the same distance. Otherwise, this will also entail a serious change in the structure and device of the mounting plate - to move the receiving holes in the plate under the stack coaxially with the new, excellent performance of the input and output columns of the stack, through which it is fed with electrolyte.

The claimed device is a functional layout for studying the structure and demonstrating the operation of a redox flow battery. It is a material base for getting acquainted with the main and mandatory functional units of this type of energy storage, as well as for conducting scientific, practical and laboratory work as part of various teaching courses on familiarization with HIT in the field of distributed energy. In order to increase interest in the subject of study, it is implemented with the possibility of self-attaching the stack to the mounting plate with reservoirs for electrolyte and a pump module. It is also intended for carrying out full-scale tests of redox flow batteries on electrolytes of various composition with a volume of up to 1.5 liters per tank and a total volume of 3 liters. The device can operate autonomously and, at the same time, act as a chemical current source for the consumer with voltage requirements of 12 V and current of 0.5 - 1.0 A from the battery state of charge close to the maximum.

Optionally, the possibility of attaching a series of stacks of various capacities and overall dimensions and shapes can be realized.

The stand can (in addition to educational functions) be built into interactive layouts of cities and other infrastructure facilities, performing the function of a prototype of a stationary energy storage device and autonomously supply energy as needed.

Thus, the claimed set of essential features provides ample functionality of educational and methodological equipment, a functional layout for studying the structure and demonstrating the operation of a flow redox battery.

Brief description of the drawings

The claimed invention is illustrated by drawings, where figure 1 is an image of the assembled functional layout; figure 2 - image of the charge-discharge module (stack); figure 3 - the upper part of the mounting plate; figure 4 - related materials to the functional layout.

Implementation of the invention

Below is a more detailed description of the claimed invention "layout", which does not limit its essence, presented in an independent claim, but only demonstrates the possibility of implementing the purpose with the achievement of the claimed technical result.

The proposed invention consists of a mounting plate (1) with electrolyte reservoirs (2), which are attached between the layers of sheet materials that make up the mounting plate: duralumin plates (3) and (4), fluororubber gaskets (5) and (6), as well as a Teflon plate (7). Achieving hermetic fastening of tanks (2) and the entire structure as a whole occurs with the help of screws (8) and nuts (9) located along the periphery and in the central part of the plate. A pump module is attached to its lower part, which includes the pump itself (10), two diamond-shaped duralumin plates (11), and cylinders (12). Fastening is done with nuts (13) and studs (14) located at the bottom of the pump module. Inside the tanks (2) are PVDF pipes (15) screwed into the bottom of the mounting plate (1). Isolation of electrolytes from atmospheric oxygen occurs by closing the tanks with lids (16). The stack (17) is inserted by the narrow part of the supply posts (18) into special grooves (19) located in the central part of the mounting plate (1). After that, using nuts (9) and four elongated studs (20), the stack is pressed against the mounting plate (1) by cross-tightening the nuts (9) located at the bottom of the plate. Then, with similar nuts, it is attracted from above. The sealing of the contact point of the stack (17) and the mounting plate (1) is carried out with the help of fluororubber gaskets (21) inserted into the slots (19). The movement of the electrolyte is carried out by means of a pump in the direction: from the tank, through the Teflon plate to the stack and back to the same tank. The electrolyte located in another reservoir has a similar movement pattern.

The model is safe to use, has small overall dimensions (280*145*375 mm) and low weight (4.95 kg), which in no way restricts the user from moving and using it in different places and areas.

The proposed invention can be used in various scientific, practical and laboratory work, workshops. The layout makes it possible to explore the functionality of stacks (charge-discharge modules / MEA batteries) of different power, and, as a result, dimensions. It has the ability to act as a chemical current source in self-sufficiency, supplying the consumer with parameters up to 12 V and 1 A for some time (depending on various factors: the concentration of the electroactive component of the electrolyte, the exact requirements of the consumer, their constancy, etc.). Allows the connection of various installations and devices for testing HIT (potentiostats-galvanostats / stations for testing batteries, etc.). It has an operating voltage range of 8-16 V and an output power of 12 W in self-sufficient conditions for 18 W in peak consumption.

On the proposed invention, it is possible to conduct such workshops, scientific, practical and laboratory work as:

1) carrying out cyclic charge-discharge tests of the “dummy” (life tests);

2) study of the process of charging an electrolyte (battery/stack) by galvanic and potentiostatic methods, as well as a combination of these methods;

3) study of the influence of the concentration of an electroactive substance on the energy intensity, the duration of the charge-discharge cycle and the consequences arising from this;

4) study of the influence of the electrolyte flow rate on the main indicators of the PRB: energy/charge/voltage efficiency;

5) removal of the current-voltage characteristic (CVC) of the stack at a battery charge level of 50 and (or) 100%;

6) study of the impact of differences in consumer requirements on the battery life in self-sustaining mode;

7) carrying out activities to popularize such an area of scientific activity as alternative energy and energy storage from renewable energy resources;

8) study of the potential distribution process for all MEAs included in the stack.

Claims (9)

Fig. 1. Functional layout consisting of a mounting plate, which includes fluororubber gaskets that isolate the electrolyte flow in the Teflon plate from duralumin plates designed to stiffen the structure, a pump module designed to ensure the circulation of electrolytes through the stack, fixed on the bottom of the mounting plate through hermetic fluororubber gaskets, as well as a stack that has the ability to control the distribution of potential across all membrane-electrode blocks, providing the process of converting chemical energy stored in the electrolyte into electrical energy, also attached to the mounting plate, but already from above, using nuts and clamping force through fluororubber gaskets and providing, during discharge, with energy both the pumping module pumping the electrolyte and the consumer. 2. Functional layout according to claim 1, characterized in that all connections are made without the use of hoses and with the help of clamping force. 3. Functional layout according to claim 1, characterized in that it has the ability to act as a chemical current source in self-sustaining mode. 4. Functional layout according to claim 1, characterized in that the method of attaching the stack to the mounting plate allows testing stacks of various overall dimensions and, as a result, power. 5. Functional layout according to claim 1, characterized in that it has an industrial design, illustrating the actual appearance of the PRB. 6. Functional layout according to claim 1, characterized in that the stack can be attached to and removed from the mounting plate by the user, which adds interactivity and interest to working with it. 7. Functional layout according to claim 1, characterized in that the stack has a classic version of electrolyte supply: two inlets and two outlets. 8. Functional layout according to claim 1, characterized in that the useful volume of the electrolyte tanks is 3 liters (1.5 for each tank). 9. Functional layout according to claim 1, characterized in that its design allows for the replacement (draining and filling) of the electrolyte, followed by its isolation from the environment using plugs.

Images