Metal-aqueous battery, and hydrogen generation and carbon dioxide storage system including the same

Abstract

To provide a metal-aqueous battery improved in the current generation amount and the current generation rate.SOLUTION: The metal-aqueous battery includes a double cell in which a pair of single cells and a current collector CC interposed therebetween are stacked. Each of the single cells comprises an anode 30, a cathode 50, a separator 40 interposed between the anode and the cathode, and a cathode spacer 60 interposed between the separator and the cathode to form a gap between the separator and the cathode. The cathodes of the single cells face each other across the current collector.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a metal-water battery and a hydrogen production and carbon dioxide storage system including the same. [Background technology]

[0002] In recent years, research into electrochemical water electrolysis has been actively conducted in line with the development of renewable energy to cope with climate change. 2 ) capture, storage and transformation technologies are becoming increasingly important.

[0003] Zinc / aluminum (Zn / Al) based aqueous battery systems are a very economical metal cathode candidate in terms of cost and reserves. Zinc / aluminum (Zn / Al) based aqueous battery systems produce hydrogen and simultaneously convert carbon dioxide into KHCO 3 This is a system that captures the metal in the form of a salt.

[0004] However, since existing metal-water batteries are single cells consisting of one anode and one cathode and stacks based thereon, the current obtainable from the batteries is limited. Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a metal water battery having an improved current generation amount and current generation speed.

[0006] An object of the present invention is to provide a metal-water battery capable of preventing the anode from being passivated.

[0007] The object of the present invention is not limited to the object mentioned above. The object of the present invention will become clear from the following description and will be realized by the means and combinations thereof described in the claims. [Means for solving the problem]

[0008] A metal water based battery according to an embodiment of the present invention includes a double cell in which a pair of single cells including an anode, a cathode, and a separator located between the anode and the cathode are stacked with a current collector sandwiched between the single cells so that the cathodes face each other, and the single cell may include a cathode spacer located between the separator and the cathode to form a gap between the separator and the cathode.

[0009] The single cell may be in the form of a plate of a predetermined thickness including a first main surface and a second main surface opposite to the first main surface, and may further include a plate located on the outer periphery of the single cell and including an internal space open toward the first main surface.

[0010] The anode may be contained within the interior space.

[0011] The separation membrane may be laminated on the first main surface and cover an open surface of the internal space.

[0012] The plate may include a first electrolyte inlet formed in a portion of a side surface and communicating with the internal space; and a first electrolyte outlet formed at a position spaced a predetermined distance from the first electrolyte inlet and communicating with the internal space.

[0013] The anode may be in the form of a pellet, and the single cell may further include a support disposed at an angle in the internal space and including a plurality of through holes, the anode being accommodated between an inner surface of the plate and the support, and a diameter of the through holes may be smaller than a diameter of the anode.

[0014] The anode may be in a sheet form, and the single cell may further include a pressure unit that is housed in the internal space and is disposed between an inner surface of the plate and the anode to provide a pressure to move the anode toward a separation membrane.

[0015] The anode may include at least one selected from the group consisting of lithium (Li), sodium (Na), magnesium (Mg), zinc (Zn), aluminum (Al), and combinations thereof.

[0016] The device may further include a conductive wire electrically connecting the anode and a current collector.

[0017] The cathode may include a precious metal catalyst supported on a carrier.

[0018] The metal water based battery further includes a separator spacer positioned between the plate and the separator, the separator spacer having a certain thickness and a frame shape with an open center, the separator spacer supporting an edge of the separator and expanding an internal space of the plate by the thickness of the separator spacer.

[0019] The metal-water battery may further include a protective film having a shape corresponding to the open surface of the plate, disposed on the open surface of the plate, and being porous.

[0020] The separation membrane may include a material having cation conductivity or anion conductivity.

[0021] The cathode spacer may have a frame shape with an open center and support an edge of the separator to form the gap, and the cathode spacer may include: a second electrolyte inlet portion formed in a portion of a side region of the cathode spacer and communicating with the gap; and a second electrolyte outlet portion formed in a portion of a side region of the cathode spacer at a position spaced a predetermined distance from the second electrolyte inlet portion and communicating with the gap.

[0022] The metal water based battery may further include a first electrolyte contained in the interior spaces of the plates; and a second electrolyte contained in the gaps.

[0023] The first electrolyte may include an alkali metal hydride.

[0024] The second electrolyte may include hydrogen ions and bicarbonate ions.

[0025] The temperature of the first electrolyte may be between 40°C and 80°C.

[0026] The temperature of the second electrolyte may be between 40°C and 80°C.

[0027] The temperature of the first electrolyte may be the same as or higher than the temperature of the second electrolyte.

[0028] The metal-water battery may include a stack of a plurality of double cells.

[0029] A hydrogen generation and carbon dioxide storage system according to an embodiment of the present invention may include the metal-water based battery; a first electrolyte supplying unit that supplies a first electrolyte to the metal-water based battery; a second electrolyte supplying unit that supplies a second electrolyte to the metal-water based battery; a first heating means positioned between the metal-water based battery and the first electrolyte supplying unit; and a second heating means positioned between the metal-water based battery and the second electrolyte supplying unit.

[0030] The first heating means may include a first heat exchanger that exchanges heat between the first electrolyte and a heat source, and the second heating means may include a second heat exchanger that exchanges heat between the second electrolyte and a heat source. Effect of the Invention

[0031] According to the present invention, it is possible to obtain a metal water battery having an improved current generation amount and current generation rate. According to the present invention, a metal water battery capable of preventing passivation of the anode can be obtained. The effects of the present invention are not limited to those mentioned above, and should be understood to include all effects that can be inferred from the following description. [Brief description of the drawings]

[0032] [Figure 1] FIG. 1 is a diagram showing a first embodiment of a metal water battery according to the present invention. [Diagram 2] FIG. 2 is a diagram for explaining the flow of electrolyte in the metal water battery according to the present invention. [Diagram 3] FIG. 2 shows a plate according to the present invention. [Figure 4A] FIG. 1 shows a first embodiment of a support according to the present invention. [Figure 4B] FIG. 2 shows a second embodiment of a support according to the present invention. [Figure 4C] FIG. 4 shows a third embodiment of a support according to the present invention. [Diagram 5] FIG. 2 is a diagram showing a second embodiment of a metal water battery according to the present invention. [Figure 6] FIG. 2 shows a cathode spacer according to the present invention. [Figure 7] FIG. 1 shows a stack according to the present invention. [Figure 8] FIG. 1 illustrates a hydrogen production and carbon dioxide storage system according to the present invention. [Figure 9] 1 is a discharge graph of a metal water battery with a double cell (DC) structure and a metal water battery with a single cell (SC) structure in Experimental Example 1. [Figure 10] 1 is a graph showing discharge versus current density for a metal water battery operated at different temperatures of the first electrolyte in Experimental Example 2. [Figure 11] 11 is a graph showing discharge over time in a metal water battery operated at different temperatures of the first electrolyte in Experimental Example 2. [Figure 12] 1 shows the results of evaluation of a metal water battery operated at different temperatures of the second electrolyte in Experimental Example 3. [Figure 13] 1 is a discharge graph of a metal water battery operated under conditions 1 to 3 in Experimental Example 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] The above objects, other objects, features and advantages of the present invention will be easily understood from the following preferred embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed contents can be thorough and complete, and so that the idea of ​​the present invention can be fully conveyed to those skilled in the art.

[0034] While describing each figure, like reference numerals are used for like components. In the accompanying drawings, the dimensions of structures are shown exaggerated for clarity of the present invention. Terms such as first and second may be used to describe various components, but these components should not be limited by such terms. These terms are used only for the purpose of distinguishing one component from another component. For example, the first component may be named the second component, and similarly, the second component may be named the first component, without departing from the scope of the present invention. A singular expression includes a plural expression unless otherwise specified in the context.

[0035] In this specification, the terms "comprise" or "have" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and should be understood as not precluding the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. In addition, when a layer, film, region, plate, or other part is described as being "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where there is another part therebetween. Similarly, when a layer, film, region, plate, or other part is described as being "under" another part, this includes not only the case where it is "directly under" the other part, but also the case where there is another part therebetween.

[0036] Unless otherwise stated, all numbers, values ​​and / or expressions expressing amounts of ingredients, reaction conditions, polymer compositions and formulations used herein should be understood in all cases to be modified by the term "about" in that these numbers are approximations reflecting various uncertainties of measurement that arise in obtaining such values ​​from disparate entities. Also, when numerical ranges are disclosed in this description, such ranges are continuous and include all values ​​from the minimum value to the maximum value, including the maximum value, unless otherwise stated. Furthermore, when such ranges indicate integers, they include all integers from the minimum value to the maximum value, including the maximum value, unless otherwise stated.

[0037] Fig. 1 is a diagram showing a first embodiment of a metal water battery according to the present invention. For ease of explanation and understanding, a first electrolyte A and a second electrolyte B are not shown in Fig. 1. Fig. 2 is a diagram for explaining the flow of electrolytes in the metal water battery according to the present invention.

[0038] The metal water based battery may include a double cell (DC) in which a pair of single cells (SC), each including an anode 30, a cathode 50, and a separator 40 located between the anode 30 and the cathode 50, are stacked with a current collector CC sandwiched between them so that the cathodes 50 face each other.

[0039] The current collector CC may be made of an electrically conductive material, for example, a thin plate made of stainless steel plated with gold (Au).

[0040] 1 and 2, the single cell SC may include a plate 10, a plate-shaped support 20 installed in an internal space 14 of the plate 10, an anode 30 accommodated between the plate 10 and the support 20, a separation membrane 40 stacked on the plate 10, a first electrolyte A accommodated in the internal space 14 of the plate 10, a cathode 50 located on the separation membrane 40, a cathode spacer 60 located between the separation membrane 40 and the cathode 50 to form a gap G between the separation membrane 40 and the cathode 50, and a second electrolyte B accommodated in the gap G.

[0041] 3 is a diagram showing the plate 10. The plate 10 may have a plate shape of a predetermined thickness including a first main surface 11, a second main surface 12 opposite to the first main surface 11, and a side surface 13 connecting the first main surface 11 and the second main surface 12.

[0042] The plate 10 may be made of a material that has no electrical conductivity and excellent physical properties, for example, polycarbonate.

[0043] The plate 10 may include an internal space 14 that is open toward the first main surface 11. That the internal space 14 is open toward the first main surface 11 may mean that a portion of the first main surface 11 is opened to form an open surface 11a, thereby allowing the internal space 14 to communicate with the outside.

[0044] The plate 10 may include an opening 15 in a partial region of a side surface 13, the opening 15 being open so that the internal space 14 communicates with the outside. For example, with reference to Fig. 1, the opening 15 may be present in a partial region of the upper side of the plate 10. An anode 30 can be supplied to the internal space 14 from the opening 15.

[0045] The metal water battery may further include a lid D detachably installed on the opening 15. There is no particular limitation on the size of the lid D as long as it can completely cover the opening 15 and isolate the internal space 14 from the outside. Meanwhile, the lid D may be made of a material that is not reactive with the first electrolyte A and the anode 30.

[0046] The plate 10 may include a first electrolyte inlet 16 formed through a portion of a side surface 13 and communicating with the internal space 14, and a first electrolyte outlet 17 formed through the side surface 13 at a predetermined distance from the first electrolyte inlet 16 and communicating with the internal space 14. For example, with reference to FIG. 1, the first electrolyte inlet 16 may be present on the lower side surface 13, and the first electrolyte outlet 17 may be present on the upper side surface 13. The plate 10 may include a plurality of the first electrolyte inlet 16 and the first electrolyte outlet 17.

[0047] 4A is a diagram showing a first embodiment of the support 20. As shown in FIG. 1, the support 20 may be installed at an incline so that the space in which the anode 30 is accommodated becomes narrower toward the bottom. When the anode 30 is ionized and its size decreases, it is neatly stacked on the bottom. This increases the contact area between the anode 30 and the support 20, and the ionization of the anode 30 can occur more easily. When the contact area between the anode 30 and the support 20 increases, the ionization area increases, and the current density of the battery can increase.

[0048] The support 20 may include an electrically conductive metal. The support 20 may also include a material having sufficient rigidity to withstand the weight of the anode 30. For example, the support 20 may include a stainless steel mesh.

[0049] The metal water battery may include a conductor 70 that electrically connects the support 20 and the current collector CC. The configuration for electrically connecting them is not particularly limited. For example, a lead L may be attached to the inner surface of the opening 15 of the plate 10 such that one end of the lead L is exposed to the outside, and one end of the support 20 may be placed in contact with the lead L, and then the conductor 70 may be connected to one end of the lead L.

[0050] The support 20 may include a number of through-holes 21. The first electrolyte A can move through the through-holes 21.

[0051] The support 20 must prevent the anode 30 from escaping the space between the plate 10 and the support 20, and therefore the diameter of the through hole 21 may be smaller than the diameter of the anode 30. Specifically, the diameter of the through hole 21 may be 0.5 mm to 2 mm.

[0052] 4B is a diagram showing a second embodiment of the support 20. In a preferred embodiment, the diameter of the through-hole 21 of the support 20 may become smaller toward the bottom. The anode 30 becomes smaller in size as it reacts and moves downward, and at this time, the moved and reduced anode 30 is prevented from slipping out of the through-hole 21.

[0053] 4C is a diagram showing a third embodiment of the support 20. The bottom side of the support 20 may not have the through-hole 21. This increases the contact area of ​​the anode, which has been reduced in size by the reaction, with the support on the bottom side, and thus the reaction can be induced quickly.

[0054] The anode 30 may be any material that can be ionized in the first electrolyte to generate electrons, and may include at least one selected from the group consisting of lithium (Li), sodium (Na), magnesium (Mg), zinc (Zn), aluminum (Al), and combinations thereof. Preferably, the anode 30 may include at least one selected from the group consisting of magnesium (Mg), zinc (Zn), aluminum (Al), and combinations thereof. Magnesium (Mg), zinc (Zn), and aluminum (Al) are preferred in aqueous systems because they are stable in water. More preferably, the anode 30 may include at least one selected from the group consisting of zinc (Zn), aluminum (Al), and combinations thereof. Zinc (Zn) and aluminum (Al) are more preferred in terms of world reserves and price.

[0055] The anode 30 may be in the form of a pellet, such as a sphere, an ellipse, or a cylinder. If the anode 30 is elliptical, the diameter is the length of the major axis. If the anode 30 is cylindrical, the diameter is the diameter of the bottom surface. The diameter of the anode 30 may be 3 mm to 10 mm. If the diameter of the anode 30 is less than 3 mm, the size of the anode 30 may be reduced by ionization and may pass through the through-hole 21. If the diameter of the anode 30 exceeds 10 mm, the specific surface area of ​​the anode 30 may be reduced, resulting in a decrease in the performance of the metal-water battery.

[0056] Fig. 5 is a diagram showing a second embodiment of the metal water battery according to the present invention. In Fig. 5, unlike Fig. 1, the anode 30 may be in a sheet form.

[0057] The metal-water battery may include a pressurizing unit 600 that is accommodated in the internal space 14 of the plate 10 and is disposed between the inner surface of the plate 10 and the anode 30 to provide a pressurizing force to move the anode 30 toward the separator 40.

[0058] A plurality of the anodes 30 may be stacked and accommodated between the pressurizing unit 600 and the separator 40 .

[0059] The pressurizing unit 600 may press the anode 30 toward the separator 40 so that the anode 30 closest to the separator 40 may start to react and be consumed.

[0060] The pressure unit 600 may include a support plate 610 for applying pressure to the anode 30 , and an elastic member 620 disposed between the support plate 610 and the plate 10 for applying an elastic force to the support plate 610 .

[0061] When the anode 30 closest to the separator 40 is consumed due to a reaction, the support plate 610 presses the anode 30 due to the elastic force of the elastic member 620. Thus, the anode 30 can be positioned closely to the separator 40 side.

[0062] The metal water based battery may further include a separator spacer 80 located between the plate 10 and the separator 40, having a certain thickness and a frame shape with an open center.

[0063] The separation membrane spacer 80 supports the edge of the separation membrane 40 and can expand the internal space 14 of the plate 10 by the thickness of the separation membrane spacer 80. The thickness of the separation membrane spacer 80 is not particularly limited, and may be 5 mm to 20 mm.

[0064] The metal-water battery may further include a protective film 90 having a shape corresponding to the open surface 11 a of the plate 10 and disposed on the open surface 11 a of the plate 10 .

[0065] The protective film 90 may be made of a material having excellent chemical resistance, such as rubber, resin, silicon, or metal.

[0066] The protective film 90 may be porous. Therefore, the protective film 90 is impregnated with the first electrolyte, and the potassium ions (K + ) or sodium ion (Na + ) etc. can migrate to the separation membrane 40.

[0067] The protective film 90 can prevent the separation film 40 from sagging. That is, the protective film 90 can act as a physical support for the separation film 40.

[0068] The separation membrane 40 may include a material having cation conductivity. For example, the separation membrane 40 may include a perfluorosulfonic acid resin such as Nafion. Therefore, the separation membrane 40 can allow the movement of cations between the anode 30 and the cathode 50, but can block the movement of the first electrolyte A and the second electrolyte B.

[0069] The separation membrane 40 may include a material having anion conductivity. For example, the separation membrane 40 may include at least one selected from the group consisting of poly(terphenylene), 1,4-diazabicyclo[2,2,2]octane-poly(ether sulfone), poly(aryl piperidinium), poly(phenylene oxide)-block-poly(vinyl benzyl trimethyl ammonium), and combinations thereof. Thus, the separation membrane 40 allows the passage of anions between the anode 30 and the cathode 50, but can block the movement of the first electrolyte A and the second electrolyte B.

[0070] The thickness of the separation membrane 40 is not particularly limited and may be, for example, 25 μm to 250 μm.

[0071] The area of ​​the separation membrane 40 may be larger than the area of ​​the open surface 11a of the plate 10. In addition, the separation membrane 40 covers the entire open surface 11a, thereby preventing the first electrolyte A from leaking out.

[0072] 6 is a view showing the cathode spacer 60. The cathode spacer 60 may be located between the separator 40 and the cathode 50. The cathode spacer 60 has a frame shape with an open center and supports the edge of the separator 40 to form a gap G between the separator 40 and the cathode 50. The cathode spacer 60 may have a thickness of 5 mm to 20 mm.

[0073] The cathode spacer 60 may comprise a chemically resistant material that does not react with the second electrolyte B. For example, the cathode spacer 60 may comprise polycarbonate.

[0074] The cathode spacer 60 may include a second electrolyte inlet 61 formed through a portion of a side surface of the cathode spacer 60 and communicating with the gap G, and a second electrolyte outlet 62 formed through a portion of a side surface of the cathode spacer 60 at a predetermined distance from the second electrolyte inlet 61 and communicating with the gap G. For example, with reference to FIG. 6, the second electrolyte inlet 61 may be present on a lower side surface, and the second electrolyte outlet 62 may be present on an upper side surface. The cathode spacer 60 may include a plurality of second electrolyte inlet portions 61 and second electrolyte outlet portions 62.

[0075] The cathode 50 may include a precious metal catalyst supported on a carrier. The type of the carrier is not particularly limited and may include, for example, at least one selected from the group consisting of carbon paper, carbon fiber, carbon felt, carbon black, carbon cloth, metal foam, metal thin film, and combinations thereof. The type of the precious metal catalyst is not particularly limited and may include, for example, platinum (Pt).

[0076] As shown in Fig. 7, the metal water battery may include a stack in which a plurality of the double cells DC are stacked. The number of the double cells DC stacked is not particularly limited and can be appropriately adjusted according to the desired current generation amount.

[0077] One of the technical features of the present invention is that the passivation of the anode 30 is prevented and the current generation rate is improved by increasing the temperatures of the first electrolyte A and the second electrolyte B in the metal water battery.

[0078] The pH of the first electrolyte A and the second electrolyte B may be as follows: - Primary electrolyte A: pH 14 or higher - Secondary electrolyte B: pH 7~9

[0079] When the pH of the first electrolyte A and the second electrolyte B is within the above range, a sufficient reaction can occur.

[0080] The first electrolyte A may contain an alkali metal hydroxide. Preferably, the first electrolyte A may contain at least one selected from the group consisting of potassium hydroxide (KOH), sodium hydroxide (NaOH), and combinations thereof. The concentration of the first electrolyte A may be 3M to 6M. When the concentration of the first electrolyte A is 6M, potassium ions (K + ), sodium ion (Na + ) is made into a saturated solution, and if the concentration is less than 3M, the metal may not be sufficiently ionized, so that a concentration of 3M to 6M of the first electrolyte A may be appropriate.

[0081] The temperature of the first electrolyte A may be 40° C. to 80° C. If the temperature of the first electrolyte A is less than 40° C., it may be difficult to obtain the effect of preventing the anode 30 from being passivated.

[0082] The second electrolyte B may contain hydrogen ions and bicarbonate ions. Preferably, the second electrolyte B is potassium bicarbonate (KHCO 3 ), sodium bicarbonate (NaHCO 3 ) and combinations thereof.

[0083] The substance supplied from the second electrolyte supply unit 300 described later is carbon dioxide (CO 2Any substance can be used as long as it dissolves and fills the inside of the cell (gap: G) with a pH of 7 to 9 and contains hydrogen ions and bicarbonate ions. For example, potassium hydroxide, potassium carbonate, potassium hydrogen carbonate, sodium hydroxide, sodium carbonate, and sodium hydrogen carbonate can be used.

[0084] The concentration of the second electrolyte B may be 0.5 M to 3 M. If the concentration of the second electrolyte B is less than 0.5 M, it may affect the reaction rate due to the increase in pH, and if it is 3 M, the potassium ion (K + ), sodium ion (Na + ) is made, the range may be appropriate.

[0085] The temperature of the second electrolyte B may be 40° C. to 80° C. When the temperature of the second electrolyte B is within this range, the resistance in the metal water battery can be reduced and the occurrence of overvoltage can be prevented.

[0086] The first electrolyte A and the second electrolyte B may be preheated to the above-mentioned temperature ranges and then provided to the metal water based battery. Preferably, the temperature of the first electrolyte A may be the same as or higher than the temperature of the second electrolyte B. Since increasing the activation of the anode 30 is important in the overall reaction, the temperature of the first electrolyte A may be relatively important. Therefore, in consideration of the overall reaction, it is better that the temperature of the first electrolyte A is the same as or higher than the temperature of the second electrolyte B.

[0087] The temperatures of the first electrolyte A and the second electrolyte B can be increased by installing a heater outside the metal water battery, or can be increased by using a first heating means 400 and a second heating means 500, as described below. A preferred method for adjusting the temperatures of the first electrolyte A and the second electrolyte B will be described.

[0088] 8 is a diagram showing a hydrogen generation and carbon dioxide storage system according to the present invention. The system may include the above-mentioned metal water based battery 100, a first electrolyte supply unit 200 for supplying a first electrolyte to the metal water based battery 100, a second electrolyte supply unit 300 for supplying a second electrolyte to the metal water based battery 100, a first heating means 400 located between the metal water based battery 100 and the first electrolyte supply unit 200 and exchanging heat between the first electrolyte and a heat source, and a second heating means 500 located between the metal water based battery 100 and the second electrolyte supply unit 300 and exchanging heat between the second electrolyte and a heat source.

[0089] The first heating means 400 allows heat from a heat source to be transferred to the first electrolyte, thereby increasing the temperature of the first electrolyte. Also, the second heat exchanger 500 allows heat from a heat source to be transferred to the second electrolyte, thereby increasing the temperature of the second electrolyte. The first heating means 400 and the second heating means 500 may include heat exchangers as a non-limiting example.

[0090] The type of the heat source is not particularly limited, and may include, for example, exhaust gas from power plants, vehicles, landfills, etc., waste heat water, and the like.

[0091] The operation of the system will now be described with reference to Figures 1, 2 and 8.

[0092] The first electrolyte supply unit 200 supplies the first electrolyte A to the metal water based battery 100 through the first electrolyte inlet unit 16. At this time, the first electrolyte A is heated to 40° C. to 80° C. by heat from a heat source in the first heating means 400.

[0093] The first electrolyte A flows into the internal space 14 of the plate 10 through a first electrolyte inlet 16 .

[0094] When the anode 30 comes into contact with the first electrolyte A, the anode 30 is ionized to generate electrons. The electrons move along the support 20, the lead portion L, and the conductive wire 70 to the current collector CC, and then are transferred to the cathode 50.

[0095] The alkali metal ions, preferably potassium ions (K + ) or sodium ion (Na + ) migrates through the separation membrane 40 to the cathode 50.

[0096] The second electrolyte supply unit 300 supplies the second electrolyte B and carbon dioxide to the metal water based battery 100 through the second electrolyte inlet unit 61. At this time, the second electrolyte B is heated to 40° C. to 80° C. by heat from a heat source in the second heating means 500. The system may further include a carbon dioxide supplying device (not shown) for supplying carbon dioxide to the second electrolyte supply unit 300. Alternatively, the second electrolyte supply unit 300 may supply an electrolyte in which carbon dioxide is dissolved.

[0097] The second electrolyte B and carbon dioxide are supplied to the cathode 50 through a second electrolyte inlet 61. In the cathode 50, the following chemical dissolution reaction of carbon dioxide occurs. [ka]

[0098] Thereafter, the following hydrogen evolution reaction occurs at the cathode 50: [ka]

[0099] In addition, carbon dioxide is stored in the cathode 50 in the form of a salt as described below. [ka]

[0100] The above H 2 and KHCO 3 (or NaHCO 3 ) is discharged to the outside of the battery through the second electrolyte outlet 62 together with the second electrolyte.

[0101] Other embodiments of the present invention will be described in more detail below using experimental examples. The following experimental examples are merely illustrative examples for aiding understanding of the present invention, and are not intended to limit the scope of the present invention.

[0102] Experimental Example 1 The cell performance was evaluated by driving a double-cell DC as shown in Figure 1. In addition, a single-cell SC-structured metal-water battery was prepared and its cell performance was also evaluated. 9 is a discharge graph of a metal water battery with a double-cell DC structure and a metal water battery with a single-cell SC structure. The metal water battery with a double-cell DC structure shows a higher cell potential at the same current. This shows that a higher current can be stably obtained in the metal water battery with a double-cell DC structure of the present invention.

[0103] Compared to metal water batteries with multiple single-cell SC structures, double-cell DC structure metal water batteries can reduce and eliminate parts such as cathode manifolds, current collectors, and conductors, allowing for the manufacture of more compact cells. Furthermore, compared to controlling multiple single-cell SCs individually, the number of control factors can be reduced by half by utilizing double-cell DC.

[0104] Experimental Example 2 The metal water battery having a double-cell DC structure as shown in FIG. 1 was operated while varying the temperature of the first electrolyte to 20° C., 40° C., 60° C., and 80° C. The zinc utilization ratio (ZUR) of each metal water battery is shown in Table 1 below. The ZUR was calculated using the following formula.

number

[0105] [Table 1]

[0106] When the first electrolyte temperature was 20°C, a ZUR value of about 25% was exhibited, whereas when the first electrolyte temperature was 80°C, a significantly improved ZUR value of about 87% was exhibited.

[0107] Figure 10 is a graph showing the discharge versus current density of the metal water based battery operated at different temperatures of the first electrolyte. Figure 11 is a graph showing the discharge versus time of the metal water based battery operated at different temperatures of the first electrolyte. When the temperature of the electrolyte was increased, both the driving performance and the duration were improved.

[0108] Experimental Example 3 A metal-water based battery having a double-cell DC structure as shown in FIG. 1 was operated while varying the temperature of the second electrolyte to 20°C, 40°C, 60°C, and 80°C.

[0109] Figure 12 shows the evaluation results of the metal water based battery operated at different temperatures of the second electrolyte. As the temperature of the second electrolyte increased, the overvoltage of the electrode decreased. Specifically, when the temperature of the second electrolyte increased from 20°C to 40°C and from 40°C to 80°C, the overvoltage was at about 0.05V level and the resistance of the battery decreased.

[0110] Experimental Example 4 A metal-water battery with a double-cell DC structure as shown in Figure 1 was operated under the following conditions. Condition 1: First electrolyte temperature 20℃, second electrolyte temperature 20℃ Condition 2: First electrolyte temperature 80℃, second electrolyte temperature 20℃ Condition 3: First electrolyte temperature 80℃, second electrolyte temperature 80℃ FIG. 13 is a discharge graph of the metal water based battery operated under conditions 1 to 3. Conditions 2 and 3 showed similar cell performance. It can be seen that the change in performance due to an increase in electrolyte temperature has a greater effect on the temperature of the first electrolyte than on the temperature of the second electrolyte.

[0111] Although the experimental examples and examples of the present invention have been described in detail above, the scope of the present invention is not limited to the above experimental examples and examples, and various modifications and improvements made by those skilled in the art based on the basic concept of the present invention defined in the appended claims are also included in the scope of the present invention. [Explanation of symbols]

[0112] 100: Metal aqueous battery 200: 1st electrolyte supply section 300:Second electrolyte supply section 400: First heating means 500:Second heating means DC: Double cell SC: Single cell CC: Current collector 10: Plate 11: First main surface 11a: Open surface 12: Second main surface 13: Side surface 14: Internal space 15: Opening 16: First electrolyte inflow part 17: First electrolyte outflow part 20: Support 21: Through hole 30: Anode 40: Separation membrane 50: Cathode 60: Cathode spacer 61: Second electrolyte inlet portion 62: Second electrolyte outlet portion 70: Conductive wire 80: Separation membrane spacer 90: Protective membrane 600: Pressure unit 610: Support plate 620: Elastic member A: First electrolyte B: Second electrolyte D: Lid G: Gap

Claims

1. A double cell is formed by stacking a pair of single cells, each of which includes an anode, a cathode, and a separator between the anode and the cathode, with a current collector sandwiched between the single cells so that the cathodes face each other, The single cell is The metal water battery further comprises a cathode spacer disposed between the separator and the cathode to form a gap between the separator and the cathode.

2. The single cell is A plate having a predetermined thickness and including a first main surface and a second main surface opposite to the first main surface, the plate being positioned on the outer periphery of the single cell and including an internal space opened in the direction of the first main surface, The anode is contained within the interior space; 2. The metal-water battery according to claim 1, wherein the separator is laminated on the first main surface to cover the open surface of the internal space.

3. The plate is a first electrolyte inlet formed in a partial region of the side surface and communicating with the internal space; and 3. The metal water battery according to claim 2, further comprising a first electrolyte outlet portion formed at a position spaced a predetermined distance from the first electrolyte inlet portion and communicating with the internal space.

4. The anode is in the form of a pellet; The single cell further includes a support member that is inclined in the internal space and includes a plurality of through holes. the anode is contained between the inner surface of the plate and the support; The metal-water battery according to claim 2 , wherein the diameter of the through hole is smaller than the diameter of the anode.

5. The anode is in a sheet form, 3. The metal-water battery according to claim 2, wherein the single cell further comprises a pressure member that is accommodated in the internal space and disposed between the inner surface of the plate and the anode to provide a pressure to move the anode toward the separator.

6. 2. The metal-water battery according to claim 1, wherein the anode contains at least one selected from the group consisting of lithium (Li), sodium (Na), magnesium (Mg), zinc (Zn), aluminum (Al), and combinations thereof.

7. 10. The metal-water battery of claim 1, further comprising a conductive wire electrically connecting the anode and a current collector.

8. 2. The metal-water battery according to claim 1, wherein the cathode comprises a precious metal catalyst supported on a carrier.

9. The metal water based battery further includes a separator spacer disposed between the plate and the separator, the separator spacer having a certain thickness and a frame shape with an open central portion, 3. The metal water battery according to claim 2, wherein the separator spacer supports an edge of the separator and expands an internal space of the plate by a thickness of the separator spacer.

10. The metal water battery according to claim 2 , further comprising a protective film having a shape corresponding to the open surface of the plate, disposed on the open surface of the plate, and being porous.

11. 2. The metal-water battery according to claim 1, wherein the separator comprises a material having cation conductivity or anion conductivity.

12. The cathode spacer has a frame shape with an open center and supports the edge of the separator to form the gap; 2. The metal-water battery according to claim 1, wherein the cathode spacer includes: a second electrolyte inlet portion formed in a portion of a side surface of the cathode spacer and communicating with the gap; and a second electrolyte outlet portion formed in a portion of a side surface of the cathode spacer at a position spaced a predetermined distance from the second electrolyte inlet portion and communicating with the gap.

13. The metal water battery comprises: A first electrolyte contained within the interior space of the plate; and 3. The metal water battery of claim 2, further comprising: a second electrolyte contained in said gap.

14. 14. The metal-water battery of claim 13, wherein the first electrolyte comprises an alkali metal hydride.

15. 14. The metal water battery of claim 13, wherein the second electrolyte comprises hydrogen ions and bicarbonate ions.

16. The temperature of the first electrolyte is 40° C. to 80° C.; The metal water battery according to claim 13, wherein the temperature of the second electrolyte is between 40°C and 80°C.

17. 14. The metal-water battery according to claim 13, wherein the temperature of the first electrolyte is the same as or higher than the temperature of the second electrolyte.

18. 10. The metal-water battery of claim 1, comprising a stack of a plurality of double cells.

19. The metal water battery according to any one of claims 1 to 18; a first electrolyte supply unit that supplies a first electrolyte to the metal-water battery; a second electrolyte supply unit that supplies a second electrolyte to the metal-water battery; a first heating means located between the metal water battery and a first electrolyte supply unit; and a second heating means located between the metal-water battery and a second electrolyte supply.

20. the first heating means includes a first heat exchanger for exchanging heat between the first electrolyte and a heat source; 20. The hydrogen generation and carbon dioxide storage system of claim 19, wherein the second heating means includes a second heat exchanger for exchanging heat between the second electrolyte and a heat source.

Images