KR20190076322A - Redox flow battery - Google Patents

Abstract

The present invention relates to a redox flow battery. More particularly, the present invention relates to a redox flow battery which comprises: a plurality of cell units including a separator through which ions pass, and a flow path frame stacked on both surfaces of the separator and having flow paths through which a positive electrode electrolyte and a negative electrode electrolyte pass; and at least three current collecting modules disposed between cell units adjacent to both ends of the plurality of cell units. The cell units are arranged in a line so that the same poles are in contact with each other through the current collecting module, so that the volume of a battery can be minimized when the redox flow battery is configured in parallel.

Description

Redox flow battery < RTI ID = 0.0 >

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a redox flow cell, and more particularly, to a redox flow battery capable of solving a structural problem that occurs when a redox flow cell can be used in a parallel manner.

Recently, energy storage system (ESS) has been actively developed, and a secondary battery capable of charging and discharging is attracting attention as a powerful technology.

The energy storage system is a system that supplies electric power to devices or systems that require electric power after storing electric power produced by thermal power, hydroelectric power, nuclear power, solar power, wind power, tidal power, cogeneration power,

For this purpose, the energy storage system is composed of a storage method using a secondary battery such as a LiB battery NaS battery, a flow battery (FB) and a super capacitor, and a non-battery storage method.

In the flow cell, there is an electrolyte containing an electroactive material. As the electrolyte flows through the electrochemical reactor, the chemical energy is converted into electrical energy. (Here, 'electroactive material' Or substances that can be absorbed by the electrode)

More specifically, in a flow cell, a positive electrode electrolyte and a negative electrode electrolyte are circulated on both sides of a membrane to perform ion exchange, and in this process, electrons move to charge and discharge. Such a flow cell is known to be most suitable for an energy storage system because it can be manufactured as a KW-MW middle-sized system with a longer life than a conventional secondary battery.

In order to increase the capacity of a secondary battery by using an energy storage system (ESS), a redox-flow battery in which a reaction material circulates is being spotlighted.

The redox flow battery is a synthesis of the words reduction, oxidation, and flow. It stores the electrolyte in a tank and feeds the electrolyte to the area called the cell to charge / discharge the battery. it means.

One of such redox flow cells is disclosed in Japanese Patent Application Laid-Open No. 10-1176126, wherein a bipolar plate and a positive electrode membrane negative electrode are formed of one cell, and an electrolyte injected into one side in a structure in which a plurality of cells are stacked in series, And a Teflon-Zirconia short-circuit prevention pipe is provided in the passage hole of the bipolar plate having different polarities when passing therethrough, thereby preventing the electrolyte from having different polarities from contacting the bipolar plate and preventing the efficiency from being lowered by short- A redox flow cell structure is shown.

However, in the conventional redox flow battery, when the cells constituting the battery are connected in series and a problem occurs in any one of the cells connected in series to each other, the performance of the redox- There is a problem of deterioration.

In order to solve the problems of the conventional redox flow battery, there has been an attempt to connect the cells constituting the redox flow battery with the live part or the discharge part in parallel. However, in the conventional redox flow battery, In order to connect each cell and the charging part or the discharging part in parallel, two or more current collecting plates have to be combined for each cell, so that there is a problem in that the volume of the cell is increased, and a collector plate made of a copper material is directly connected to the electrolyte The O-ring must be positioned in the electrolyte flow passage formed on the current collecting plate to prevent the separator and the current collector plate from being separated from each other by the O-ring even when the cell is squeezed to lower the energy charging and discharging performance.

Therefore, there is a need for a redox flow cell having a novel cell structure that can solve the above problems.

Patent Document 1) Korean Patent Laid-Open No. 2011-0116624 (name: redox flow battery structure, published on October 26, 2011)

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a redox flow cell capable of connecting a cell, a charger and a discharger in parallel.

Another object of the present invention is to provide a redox flow cell having a novel structure capable of solving the problem of inefficiency due to the volume of the redox flow cell being increased when a plurality of cells constituting the redox flow battery, a charging unit and a discharge unit are connected in parallel.

A method of incorporating a current collecting plate on a separator plate is provided to minimize the number of components constituting the redox flow cell.

The redox flow cell according to the present invention is a redox flow battery for circulating an electrolyte solution into a cell unit. The redox flow battery includes a separation membrane 110 through which ions are passed, A plurality of cell unit bodies (100) arranged in a line and including a flow path frame (120) in which a flow path through which a positive electrode electrolyte solution and a negative electrode electrolyte pass, respectively; And a plurality of current collecting modules (200) disposed between the cell unit bodies (100) adjacent to each other at both edge ends of the cell unit units (100) arranged in a line and the cell unit units (100) Are arranged in a line so that the flow path frames (120) of the flow paths (120) contact with each other through the current collecting module (200).

The current collecting module 200 includes a separator plate 210 through which electric charges circulating through the two flow path frames 120 are prevented from mixing with each other and a current collecting plate 220 made of a conductive material, .

The current collecting module 200 includes two separator plates 210 stacked on the inner surface of the cell unit unit 100 located on one side and the cell unit unit 100 located on the other side, And a current collecting plate 200 disposed between the separating plates 210. The plurality of first current collecting modules are disposed between the cell unit bodies 100 connected to each other with the same polarity, And a pair of second current collecting modules each composed of a separator plate 210 laminated on one side and an outermost side of the separator plate 210 and a collecting plate 200 laminated on the outside of each separator plate 210 .

The current collecting module 200 includes a current collecting module 200A in which the current collecting plate 220 is embedded on the separating plate 210 and one side of the current collecting plate 220 protrudes to the outside .

A positive electrode circuit part 310 connected in parallel to the current collecting module 200 which is an anode of the plurality of current collecting modules 200 and electrically connected to the charging part or the discharging part; And a circuit unit 300 composed of a current collecting module 200 connected in parallel and a cathode circuit unit 320 electrically connected to the charging unit or the discharging unit.

Further, the present invention is characterized by further comprising a fixing portion (400) for pressing the current collecting module (200) located at the outermost position from both sides.

In the method of embedding the current collecting plate 220 in the separating plate 210 constituting the redox flow cell, a pressing step S100 for pressing the both ends of the separating plate 210 with a fixing member whose positional displacement is limited, ; A heating step (S200) of heating a central region of the separator plate (210); A coupling groove forming step S300 in which a central region of the heated separator plate 210 expands and a coupling groove is formed by opening at one side and the other side; A current collecting plate mounting step (S400) of inserting the current collecting plate (220) into the coupling groove; And a cooling step (S500) of cooling the separator plate (210); And a coupling step (S600) for pressing and fixing the collecting plate (220) located in the coupling groove, the central region of the separating plate (210) contracting the cooled separating plate (210) and widened to one side and the other side .

Further, the fixing member closes the electrolyte flow passage L formed at the edge of the separator plate 210 in the pressing step S100.

In addition, in the heating step (S200), the separation plate 210 is heated by a heat source having a temperature of 700 to 1500 degrees.

Also, in the heating step (S200), the heat source heats the separator plate 210 for 1 to 10 seconds.

In the redox flow cell according to the present invention, the plurality of adjacent cell unit bodies constituting the redox flow cell are arranged so that the positive electrode and the positive electrode face each other, the negative electrode and the negative electrode face each other, There is an advantage that the number of collector plates necessary for connecting the live parts in parallel can be minimized.

That is, the arrangement structure of the cells is improved, and at least two current collecting plates are required for each cell when the discharge part and the charging part are connected in parallel, thereby solving the problem that the volume of the redox flow cell is increased.

Further, it is sufficient to dispose only one separator plate in which a collector plate is built in the separator plate and a current collecting plate is interposed between the flow path frames through which the electrolytic solution having the same polarity flows, thereby simplifying the configuration of the redox flow cell.

In detail, the number of components for constituting the redox flow battery is minimized, thereby reducing the production cost of the redox flow battery and allowing more cell unit bodies to be located in a limited space, Can be maximized.

1 is a conceptual view of a redox flow cell of the present invention.
FIG. 2 is an exploded perspective view of a redox flow cell according to the present invention (when the separator plate and the current collector plate are separately formed)
3 is an exploded perspective view of a redox flow cell according to the present invention.
FIG. 4 is a perspective view showing a stack of cell unit bodies and current collecting modules assembled together in the redox flow cell of the present invention. FIG.
5 is an AA cross-sectional view of a current collecting module having a current collecting plate embedded in a separating plate.
6 is a conceptual diagram showing a redox flow cell according to the present invention electrically connected to a target object.
7 is a conceptual view showing a fixing unit for pressing a stack constituting the redox flow cell of the present invention.
8 is a flowchart showing a method of incorporating a current collecting plate in a separating plate.
9 to 13 are conceptual diagrams showing a method of incorporating a current collecting plate in a separating plate.

Advantages and features of embodiments of the present invention and methods of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions in the embodiments of the present invention, which may vary depending on the intention of the user, the intention or the custom of the operator. Therefore, the definition should be based on the contents throughout this specification.

Hereinafter, a redox flow cell according to the present invention will be described with reference to the accompanying drawings.

1 is a schematic structural view for explaining a structure of a redox flow cell 1000 according to the present invention.

1, a redox flow cell according to the present invention comprises a separator 110 through which ions pass, a separator 110 disposed on both sides of the separator 110, and a flow path through which the positive electrode electrolyte and the negative electrode electrolyte pass, respectively A plurality of cell module units 100 including the formed flow path frame 120 and three or more current collecting modules 200 disposed between both ends of the plurality of cell unit units 100 and adjacent cell unit units 100 And the cell unit bodies 100 are arranged in a line so that the same poles are in contact with each other through the current collecting module 200.

A plurality of cell unit bodies 100 and a plurality of the current collecting modules 200 are crossed with each other while a flow path frame 120 in which the same polarity electrolyte flows in opposition is connected to the current collecting module 200 Thereby forming one stack 1000A constituting the redox flow battery 1000. [

More specifically, in order to connect the cells constituting the rechargeable battery, the discharging unit, and the redox flow cell in parallel, the conventional redox flow battery has to sequentially stack the separator plate and the current collector plate on both sides of the cell, A conventional redox flow cell requires a plurality of current collecting plates in comparison with a case where a stack including a plurality of cells, a separator plate, and a current collector plate is connected in series with the charging unit and the discharging unit, The volume of the stack in which the plate and the current collecting plate are gathered becomes large and the number of cells that can be located in a limited space is reduced, resulting in a problem of a decrease in charge / discharge efficiency.

1, the electrolytic solution having the same polarity is circulated in the flow path frame 120 adjacent to each other as shown in FIG. 1, so that the flow path frame 120 is interposed between the adjacent flow path frames 120, And the current collecting module 200 in which the current collecting plates made of a conductive material are gathered can be disposed on the flow path frame 120 (120) constituting each cell unit body (100) The present invention solves the problem of increasing the thickness of the stack, which occurs when the current collecting module 200 is individually disposed at each edge of the stack.

The reason that the electrolytic solution having the same polarity is introduced into the adjacent channel frames 120 is that in the case of the channel frame 120 located at the outermost one of the plurality of channel frames 120 constituting the stack, The electrolyte solution having the same polarity as that of the adjacent flow path frame 120 flows in the case of the flow path frame 120 not positioned at the outermost periphery.

That is, when a plurality of cell unit bodies 100 and the current collecting module 200 are stacked to form one stack, the anode electrolyte tank 10 storing the anode electrolyte and the cathode electrolyte tank 20 storing the cathode electrolyte are collectively referred to as collectors The electrolytic solution having the same polarity is circulated in the flow path frame 120 constituting the different cell unit bodies 100 disposed closely to both sides of the module 200 so that the connection portions of the adjacent cell unit bodies 100 have the same polarity will be.

2 is an exploded perspective view of one cell S constituting a stack of the redox flow cell 1000 of the present invention.

Referring to FIG. 2, in the present invention, the cell S is disposed at the center, and includes a separation membrane 110 such as a membrane having a property of passing ions but not passing an electrolyte, And an electrolyte solution flowing through the flow path frame 120 is discharged to the outside of the flow path frame 120. The flow path frame 120 includes a flow path frame 120 in which a flow path through which electrolyte flows, And a current collecting plate 220 stacked on both sides of the separating plate 210. The current collecting plate 220 may be formed of a conductive material.

In detail, the edges of the current collector plate 220, the separator plate 210, the flow path frame 120, and the separator 110 have a positive electrode electrolyte inflow passage through which a positive-polarity electrolyte flows, A cathode electrolyte discharge passage through which the electrolyte is discharged, a cathode electrolyte inlet passage through which the cathode electrolyte flows, and a cathode electrolyte discharge passage through which the cathode electrolyte is discharged, and the electrolyte introduced through the cathode electrolyte inflow passage passes through the separator The electrolyte solution flowing into the channel frame 110 is discharged through the cathode electrolyte discharge passage after being contacted with one surface of the separation membrane 110 and the electrolyte solution flowing through the cathode electrolyte solution inlet passage is separated from the separation membrane 110, Flows into the flow path frame 120 stacked on the other surface of the separator 110 and comes into contact with the other surface of the separator 110 and is discharged through the cathode electrolyte discharge passage. The electrolyte solution is possible with the other polarity to each other on the other surface and one surface of the membrane 110 and the oxidation-reduction reaction will take place which can be charged and discharged.

2, the current collecting module 200 shown in FIG. 1 includes a separator plate contacting the flow path frame 120 located at one side, and a separator disposed at the other side The cell unit 100 is composed of a separator plate 210 in contact with the flow path frame 120 and a collecting plate 220 disposed between the separator plates 210 disposed on one side and the other side, A separator plate 210 disposed on the other side of the outermost one of the plurality of cell unit bodies 100 and a collecting plate 200 stacked on the outside of each separator plate 210 And a pair of second current collecting modules which are connected to each other.

In detail, when a plurality of cell unit bodies 100 are gathered to form one stack 1000A used in a redox flow cell, the second current collector module is placed in the cell unit 100 located at the outermost position, The first current collecting module is disposed between the cell units 100 facing the same polarity to minimize the volume of the stack used in the redox flow cell.

3, the collector plate 220 of the redox flow cell 1000 according to the present invention is embedded in the separator plate 210 to form a third current collector module 200A, When the cell S is formed using the third current collecting module 200A, the cell S has a separation membrane 110 having a property of passing the electrolyte but not allowing the electrolyte to pass therethrough, And a third current collecting module 200A stacked on both side surfaces of the flow path frame 120. The current collecting module 200A includes a first current collecting module 200A and a second current collecting module 200B.

In more detail, the current collecting plate 220 is embedded in the separator 210 to minimize the number of components constituting the cell S, and further, the cell S is used as shown in FIG. 4 The third collecting module 200A is connected to both ends of the plurality of cell unit bodies 100 and a connecting portion where the respective cell unit bodies 100 are connected to each other when the stack 1000A used in the redox flow cell is formed, It is possible to minimize the thickness of the redox flow cell and to maximize the number of the cell unit bodies 100 that can be positioned in a limited space.

5, the current collecting plate 220 is embedded in the separating plate 210, and the electrolytic solution passing through the electrolytic solution passing passage is directly contacted with the current collecting plate It is possible to reduce the thickness of the stack constituting the redox flow cell.

In detail, since the current collecting plate 220 is made of a copper material, the current collecting plate 220 is oxidized when it is in direct contact with the electrolytic solution, resulting in a problem that the durability of the apparatus is inferior. An O-ring is provided on the electrolyte flow passage formed in the current collecting plate 220 to limit the direct contact of the electrolyte with the current collecting plate 220.

Therefore, in order to minimize the use of the O-ring, the current collecting plate 220 may be formed in the separating plate 210 so that the current collecting plate 220 is formed on the separating plate 210, This problem is solved by embedding the electrolytic solution so as not to come in contact with the passage through which the electrolytic solution passes.

6, the redox flow battery 1000 according to the present invention includes a plurality of current collecting modules 200 connected in parallel to a plurality of current collecting modules 200, And a cathode circuit unit 320 connected in parallel to the current collecting module 200 which is a negative one of the plurality of current collecting modules 200 and electrically connected to the charging unit or the discharging unit.

A plurality of the current collecting modules 200 in contact with the flow path frame 120 through which the positive electrode electrolyte circulates are connected to the positive electrode circuit unit 310 and a plurality of the plurality of current collecting modules 200 contacting the flow path frame 120 through which the negative electrode electrolyte circulates. The anode circuit part 310 and the cathode circuit part 320 are connected to the object 30 such as the charging part or the discharging part so that they can be charged and discharged after the cathode circuit part 320 is connected to the current collecting module 200 .

As a result, the conventional redox flow cell has a stacked structure in which a plurality of cells are stacked and a target object is connected in parallel, a channel frame constituting each cell and in which a positive electrode electrolyte circulates, and a negative electrode Since the current collecting plates are arranged at the opposite ends of each cell so that the cells of the stack constituting the stack are connected in parallel to each other, The redox flow cell 1000 of the present invention constitutes the cell unit 100 and the flow field frame 120 having the same polarity as that of the collector unit 100 is connected to the collector plate The current collecting plate 220 is disposed between the cell unit 100 and the cell unit 100 and between the cell unit 100 and the cell unit 100, It is sufficient if the number of the current collectors 220 required is N + 1 when the number of the cell unit bodies constituting the stack is (N) in order to connect the cell unit body and the object in parallel. It is.

The redox flow cell 1000 according to the present invention may further include a fixing unit 400 for pressing the current collecting module 200 located at the outermost position from both sides as shown in FIG.

In detail, each constituent element constituting the cell unit body 100 and each constituent element constituting the current collecting module 200 can be arranged more closely to each other, so that the constituent elements of the cell unit body 100 Thereby preventing an electrolyte leakage accident.

The redox flow cell 1000 according to the present invention can incorporate the current collecting plate 220 in the separating plate 210 through the method shown in FIG. 8, and the current collecting plate 220 is attached to the separating plate 210 A pressing step S100 for pressing both ends of the separating plate 210 with a fixing member whose positional displacement is limited, a heating step S200 for heating a central region of the separating plate 210, A coupling groove forming step S300 in which a central region of the plate 210 expands and extends to one side and the other side to form a coupling groove 211; A cooling step (S500) of cooling the separating plate (210), a cooling step (S500) of cooling the separating plate (210), a central region of the separating plate (210) (S600) for pressing and fixing the current collector plate (220) positioned in the first housing (211).

9, the both ends in the width direction of the separating plate 210 are fixed by the fixing member G so that both sides of the separating plate 210 in the width direction are expanded or moved And the electrolytic solution transfer passage L is closed. In the heating step S200, as shown in FIG. 10, the separator plate 210 is heated for 1 second to 10 seconds by a heat source having a temperature of 500 to 1500 degrees. 11, the central region of the separator plate 210 expands and opens upward and downward to form a coupling groove 211 at the center, as shown in FIG. 11, in the coupling groove forming step S300, The collecting plate 220 is inserted into the coupling groove as shown in FIG. 12 in the collecting plate mounting step S400, the separating plate 210 heated in the cooling step S500 is cooled, The current collector plate 220 located in the coupling groove 211 as shown in FIG. By the central region of the separating plate 210 was formed a groove 211 which is fixedly pressed.

The technical idea should not be interpreted as being limited to the above-described embodiment of the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Accordingly, such modifications and changes are within the scope of protection of the present invention as long as it is obvious to those skilled in the art.

100: cell unit
110: Membrane
120: Euro frame
130: separation plate
200: current collecting module
210: separator plate 211: engaging groove
220: Home Edition
310: anode circuit part 320: cathode circuit part
400:

Claims (10)

1. A redox flow cell for circulating an electrolyte solution into a cell unit,
And a flow path frame 120 stacked on both surfaces of the separator 110 and formed with flow paths through which the positive and negative electrode electrolytic solutions respectively pass, A cell unit 100; And
And a plurality of current collecting modules (200) disposed between both edge ends of the cell unit units (100) arranged in a row and the cell unit units (100) adjacent to each other,
Wherein the cell unit body (100) is arranged in a line so that the same flow path frame (120) contacts with each other through the current collecting module (200).
The method according to claim 1,
The current collecting module 200 includes a separator plate 210 through which electric charges circulating through the two flow path frames 120 are prevented from mixing with each other and a collecting plate 220 made of a conductive material As a redox flow cell.
3. The method of claim 2,
The current collecting module 200 includes two separator plates 210 laminated on the inner surface of the cell unit body 100 positioned on one side and the cell unit 100 positioned on the other side, And a current collecting plate 200 disposed between the separating plates 210. The plurality of first collecting modules are disposed between the cell unit bodies 100 connected to each other with the same polarity,
A pair of second collectors composed of a separator plate 210 laminated on one side and the other side of the outermost cell unit bodies 100 and a collecting plate 200 laminated on the outside of each separator plate 210, ≪ / RTI > module.
3. The method of claim 2,
The current collecting module 200 includes a current collecting module 200A in which the current collecting plate 220 is embedded on the separating plate 210 and one side of the current collecting plate 220 protrudes outward , Redox flow battery.
The method according to claim 3 or 4,
A positive polarity circuit unit 310 connected in parallel to the current collecting module 200 which is an anode among a plurality of the current collecting modules 200 and electrically connected to the charging unit or the discharging unit, And a negative electrode circuit part (320) connected in parallel to the positive electrode (200) and electrically connected to the charging part or the discharging part.
6. The method of claim 5,
Further comprising a fixing portion (400) for pressing the current collecting module (200) located at an outermost position from both sides.
A method for incorporating a current collecting plate (220) in a separator plate (210) constituting the redox flow cell of claim 4,
A pressing step (S100) of pressing both side ends of the separating plate (210) with a fixing member whose positional displacement is limited;
A heating step (S200) of heating a central region of the separator plate (210);
A coupling groove forming step S300 in which a central region of the heated separator plate 210 expands and a coupling groove is formed by opening at one side and the other side;
A current collecting plate mounting step (S400) of inserting the current collecting plate (220) into the coupling groove; And
A cooling step (S500) of cooling the separation plate (210); And
And a coupling step (S600) for pressing and fixing the current collecting plate (220) located in the coupling groove, the central region of the separating plate (210) being shrunk and separated from the one side and the other side, How to integrate the front plate into the plate.

8. The method of claim 7,
Wherein the fixing member closes the electrolyte flow passage (L) formed at the edge of the separator plate (210) in the pressing step (S100).
9. The method of claim 8,
Wherein the separation plate (210) is heated by a heat source having a temperature of 700 to 1500 degrees in the heating step (S200).
10. The method of claim 9,
Wherein the heat source heats the separator plate (210) for 1 to 10 seconds in the heating step (S200).

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