WO2022071614A1

WO2022071614A1 - Apparatus for producing high-pressure hydrogen and oxygen by using water electrolysis

Info

Publication number: WO2022071614A1
Application number: PCT/KR2020/013306
Authority: WO
Inventors: 이웅무; 이정남
Original assignee: 이웅무
Priority date: 2020-09-29
Filing date: 2020-09-29
Publication date: 2022-04-07

Abstract

The objective of the present invention is to provide an electrochemical device and method for producing high-pressure hydrogen gas. An apparatus for producing and compressing high-pressure hydrogen gas and oxygen gas by using water electrolysis, according to the present invention, provides a method for improving the structural stability of a stack and a method for removing a trace amount of impurities generated when a porous polymer separator is used. To increase structural stability, the pressures inside and outside the stack are equalized, and the outside of the stack is wrapped with an integrated reinforcing agent. An electrochemical catalytic column is used to remove impurity gas by mixing, through the separator, hydrogen gas and oxygen gas produced by two electrodes inside the stack, and in order to make the pressures of the two gases equivalent, a method for adjusting the volume occupied by oxygen gas in the entire apparatus was adopted.

Description

High-pressure hydrogen and oxygen production device using water electrolysis

The present invention relates to an energy technology for the production of high-pressure hydrogen gas for supplying hydrogen to a device requiring hydrogen fuel, and to an apparatus for producing, compressing and storing hydrogen and oxygen gas by an electrochemical method.

One of the prerequisites for practical use of next-generation electric vehicles or transportation means using hydrogen fuel cells as a power source is the smooth supply of hydrogen charging stations. If this problem is resolved, the supply of fuel cell electric vehicles, which has a great advantage over battery electric vehicles in terms of mileage, charging time, and waste battery disposal, will be expanded.

The biggest obstacle to the smooth diffusion of hydrogen charging stations is the large scale of the charging stations and high construction and maintenance costs. The construction of the charging station is summarized in the problem of securing a supply source and compression of hydrogen gas. Hydrogen supply to the charging station largely depends on three methods. The first method is the use of by-product hydrogen obtained as a by-product in an oil refinery, such as decomposition of naphtha, or as a by-product in a steel mill. Although it has the advantage of being very cheap, there are problems such as removal of impurities contained in hydrogen, high-purity purification, transportation to charging stations, and securing storage facilities. The second method is a method by reforming fossil fuels such as natural gas. Since hydrogen production by reforming is produced together with carbon dioxide gas, it is arranged for the desired purpose of hydrogen as a clean energy source. The third method is a method by water electrolysis. Although there is an advantage that the device is small and oxygen is produced together, the economic feasibility is sensitively dependent on the price of electricity.

A piston-mechanical method using a diaphragm or ionic liquid is mainly used for hydrogen compression. In order to compress hydrogen gas to a high pressure, a multi-stage compression process is required, and the size of the device increases due to the need for cooling. In addition, the mechanical compression method has disadvantages such as high noise and low energy efficiency.

As an alternative to the mechanical compression method, there is an electrochemical compression method, and many research and development are in progress (Patent Documents 1,2,3,4,5,6 Non-Patent Document 1). The electrochemical compression method does not compress gas by external pressure, but fills a closed space with gas generated by electric power continuously applied to the electrochemical cell. That is, it is an internal pressure increase method. An electrochemical cell is basically composed of two electrodes with a separator inserted therebetween. When a voltage is applied between the electrodes, an electric current flows. Accordingly, gas moves between the electrodes or hydrogen is generated from the electrodes. If the space containing the electrode is a closed system and an electric current continues to flow, the pressure of the gas increases as long as the outer wall is not crushed.

The electrochemical compression method can be divided into two types depending on the raw material supplied to the compressor. One is the electrolysis method using water. When power is supplied to this system that uses water as a raw material, hydrogen is produced at one electrode and oxygen at the other, and high-pressure hydrogen and oxygen gas are produced together by compression. Since water is supplied in parallel to each unit cell, hydrogen/oxygen production occurs simultaneously in each cell and is discharged through a common conduit. Another electrochemical method is a multi-step oxidation/reduction method using hydrogen as a raw material (Patent Document 3). The system configuration of this method using hydrogen as a raw material is similar to that of a fuel cell, and any source of hydrogen gas can be used. In this system, an oxidation/reduction reaction takes place at one electrode of the unit cell, which oxidizes hydrogen ions, a raw material, into hydrogen ions, permeates the membrane membrane, and reduces these ions back to hydrogen molecules at the other electrode. Therefore, in this method, hydrogen gas passes through each unit cell connected in series, and the pressure is gradually increased through overlapping oxidation/reduction. When the electrode area of the unit cell, the chemical composition, and the number of accumulated unit cells are the same, the hydrogen production per hour is much lower than that of the electrolysis method.

The biggest technical problems of the electrochemical hydrogen production compression method by water electrolysis introduced in the present invention are summarized in two. One is the mechanical and structural strength of the stack, which is a key element of the device, and the other is the purity of the hydrogen produced. Structural stability of a stack, which is a stack of electrodes, at high pressure is sensitively dependent on the mechanical strength of the separator inserted between the two electrodes of the unit cell and other components of the unit cell, and the local stress applied to the bonding interface of the stack. When assembling the stack, a material with a “ring” structure is used for the outer wall to withstand the pressure of the gas generated inside, and a stretchable material such as a “woven sheet” is inserted between the electrode and the bipolar distribution board. Thus (Patent Document 5) or a composite membrane in which the mechanical strength of the membrane is reinforced is used (Patent Document 6). However, when the pressure of the internal gas rises above 300 atmospheres, the reinforcement of the stack components alone is limited. In order for hydrogen filling stations to become universal, the hydrogen gas pressure in the storage container must be maintained at 700 atm or higher, and the design of the internal structure of the compression device to withstand high pressure is essential.

In order to satisfy the above conditions, it is required to select a brand new method and material. Patent Document 1 proposes a method in which hydrogen and oxygen are simultaneously produced by water electrolysis, and a part of oxygen serves as an adjuvant to help the compression of hydrogen. This method significantly reduces the size of the high-pressure hydrogen production and compression device and suggests the possibility of lowering the price of the device by using low-cost materials. The key to this method is to place a water electrolysis stack inside a housing or container and fill the inner space of the housing with high-pressure oxygen gas produced by the stack. Accordingly, it is possible to maintain the inside and outside of the stack at equal pressure, and the structural stability of the stack can be increased. The method of using equal pressure inside and outside the stack can be a great advantage of the water electrolysis method. However, this method did not provide a countermeasure against the explosive reaction that may be caused by the sudden mixing of high-pressure hydrogen and oxygen gas due to damage to the device.

Another technical problem of the high-pressure electrolyzer is the purity of the gas. In water electrolysis, as the pressure of the gas increases, the solubility of hydrogen and oxygen gas also increases according to Henry's law in the electrolyte solution circulating inside the device. Therefore, in order to increase the purity of the produced gas, it is necessary to minimize the mixing of the hydrogen gas/electrolyte solution and the oxygen gas/electrolyte solution. Under high pressure conditions, the supply of water to the water reservoir inside the stack, the equalizer of hydrogen/oxygen gas pressure, and the circulation method of the electrolyte solution must be designed differently from the circulation method in the atmospheric electrolysis device. Technical analysis and specific solutions for these problems have not been reported.

[Prior art literature]

[Patent Literature]

(Patent Document 1) 1. Ung-Moo Lee and Jeong-Nam Lee, "A device for producing and storing high-pressure hydrogen gas using water electrolysis," applied for a Korean patent (Application No. 10-2018-0029929, Filed on March 14, 2018)

(Patent Document 2) 2. F. Barber, B. Balasubramanian an M. Stone, US Patent 6,994,929 B2 (2006).

(Patent Document 3) 3. T. Y. H. Wong, F. Girard, T. P. K. Vanderhoek, US Patent Application Publication 2004/0211679 A1 (2004).

(Patent Document 4) 4. W. F. Smith and J. F. McElroy, US Patent 5,350,496 (1994).

(Patent Document 5) 5. H. Vandenborre, US Patent 6,554,978 B1 (2003).

(Patent Document 6) 6. Daejin Yoon, Sangbong Moon, "Water Electrolysis Reinforced Composite Membrane and Water Electrolysis Membrane Electrode Composite Containing Same," Korean Patent 10-1754122 (2017)

(Patent Document 7) 7. Ung-Moo Lee and Jong-Hoon Kim, "Nickel Electrode with High Surface Area and Manufacturing Method thereof," Korean Patent 10-1377076 (2014)

[Non-patent literature]

(Non-Patent Document 1)1. F. Allebrod, C. Chatzichristodoulou, M. B. Mogensen, Journal of Power Sources, 229, pp. 22-31 (2013).

(Non-Patent Document 2)2. J. H. Kim, J. N. Lee, C. Y. Yoo, K. B. Lee and W. M. Lee, International Journal of Hydrogen Energy, 40, pp. 10720-10725 (2015).

It is an object of the present invention to independently produce and compress high-pressure hydrogen gas and by-product oxygen gas for hydrogen charging by water electrolysis, and high-pressure hydrogen capable of producing high-purity gas while maintaining structural stability of the device even at high gas pressure / The purpose of this is to provide an oxygen gas production device and at the same time provide a safe device manufacturing method that eliminates the risk of a combustion reaction that may occur during abrupt mixing of hydrogen/oxygen gas.

The technical difficulties involved in producing high-pressure hydrogen and oxygen gas by water electrolysis can be summarized as follows. The first problem is the mechanical and structural stability of the module. When the gas pressure rises above 300 atm, stress management in the weak areas of device components and maintaining the stability of the separator become important. The second problem is the stability problem due to the explosion reaction caused by the sudden mixing of the two gases due to the breakage of the dividing wall separating them as the pressure of the hydrogen and oxygen gases increases. The third problem is that the solubility of gases dissolved in the electrolyte liquid (electrolyte) increases according to Henry's law as the pressure increases. Therefore, in order to increase the purity of each gas produced and compressed at high gas pressure, mixing of the hydrogen/electrolyte mixture flowing in contact with the hydrogen electrode and the oxygen/electrolyte mixture flowing in contact with the oxygen electrode should be minimized.

First, to achieve mechanical stability, pressure equalization in and out of the device components can be taken. One of the great advantages of the water electrolysis method is that hydrogen and oxygen are produced together, so if these gases are in pressure equilibrium, the stack can be placed inside a housing filled with hyperbaric oxygen to achieve equalization of the pressure applied inside and outside the stack. . If the outside of the stack is equalized to the inside and the oxygen and hydrogen gas inside the stack is equalized, the local stress can be effectively offset and the separation membrane can be effectively prevented from being damaged.

A stack manufactured by stacking unit cells is the most important component of a water electrolysis device, and when a circular electrode is used, it has a cylindrical shape. The top and bottom covers are attached to the top and bottom of the stacked unit cells of the stack and fixed with bolts and nuts, and the entire stack is bound by this force. The mechanical force applied to the internal structure of the stack by high-pressure hydrogen and oxygen gas produced by water electrolysis can be roughly divided into two types depending on the direction. One force is applied perpendicular to the surface of the unit cell, which is the unit structure of the stack (let's call it a vertical force), and the other force is applied parallel to the surface (let's call it a horizontal force, lateral force). . These forces are applied vertically or parallel to the upper and lower plates of the stack and also to the internal structure. The local stress applied to the joint surface of the bolt and the nut and the force applied to the top and bottom of the separator are representative examples of the force in the vertical direction. The radial force applied to the inner wall of the flow path formed perpendicular to the surface of the upper plate/lower plate is a good example of the force in the horizontal direction.

The structural stability of the stack under the influence of horizontal forces is illustrated by the following example. In a stack composed of a stack of unit cells, a conduit through which high-pressure gas and electrolyte flow is perpendicular to the surface of the upper plate/lower plate of the stack, and a lateral radial force is applied to the side of the inner wall. When the unit cells are stacked, a gasket skeleton is placed between the bipolar power distribution boards that create the boundary above and below the unit cells.

When constructing a unit cell, two disk-shaped gasket frames are generally used. (However, by modifying the structure of the gasket skeleton, one skeleton can also fulfill its role.) One of these two skeletons is placed in a unit cell in contact with the lower surface of the upper power distribution board, and the other skeleton is the lower power distribution board. It is placed in such a way that it is in contact with the upper surface of And a separation membrane is disposed on the contact surface of the two skeletons. Inside the gasket skeleton, a disk-shaped electrode and a porous metal layer are disposed in contact with the separator and the distribution plate, respectively. When making a stack by stacking unit cells, an “O”-ring, gasket, protrusion, or epoxy adhesive is used on the contact surface between the distribution board and the gasket skeleton and between the gasket skeleton and the separator to help in sealing.

As described above, the gasket skeleton in the unit cell contains components such as electrodes and supports a sealing O-ring or gasket that prevents leakage of gas or liquid from the unit cell, as well as providing a flow path. It plays a very important role. In other words, a decisive role of providing a flow path for the electrolyte solution flowing into each unit cell, which is a component of the stack, from outside the stack, and providing a flow path for discharging the mixture of gas and electrolyte solution generated in the unit cell electrode to the outside of the stack carry out The flow path is formed in a direction perpendicular to the flat plate of the skeleton on the outside of the stack, and becomes horizontal when passing through the porous metal layer of the unit cell. However, when assembling a stack by stacking unit cells, if the above-described flow path is made by penetrating a plurality of thin disk-shaped gasket skeletons with a thickness of 1-2 mm or less in a vertical direction and parallel to the central axis of the stack, in this structure, the stacked When the radiative force applied to the inner wall of the vertical flow path rises, the probability that the gasket skeleton will breakage increases.

Therefore, in the present invention, in order to increase the structural stability of the stack, a unitary body made of a polymer material is used as the reinforcement body of the stack, and the stack is placed in close contact with the hollow part formed inside the reinforcement body, and at the same time, the stack and the stack are formed. A method of forming a communication channel was chosen. The direction of the vertical flow path (classified as a pair of flow paths for hydrogen gas and oxygen gas type, respectively) formed in the reinforcement body is parallel to the central axis of the inner stack along its central axis, and withstands the radiative force applied to the inner wall of the flow path. The mechanical strength that can be achieved was increased significantly compared to the flow path inner wall of the laminated multiple gasket skeleton. In this configuration, the gasket skeleton of the unit cell provides only a horizontal flow path, and the original vertical flow path is modified to be closed.

In the complex structure that combines the two elements as described above, the connection for communication between the vertical flow path of the reinforcement and the horizontal unit cell flow path appears as an important problem. In order to solve this problem, a plurality of protrusions are made on the side of the gasket skeleton, which is a unit cell component, to help engage and communicate with the stack and the reinforcement. The gasket skeleton is modified to include a bridge connecting each unit cell and the flow path of the reinforcing body without removing the previous vertical flow path, and this protrusion can directly serve as a bridge. When the stack is pushed into the hollow inside the reinforcing body, this protrusion is inserted into a vertical valley formed to function as a connecting path on the inner wall of the hollow of the reinforcing body. The valley-type space serves to horizontally communicate the plurality of conduits and hollow parts inside the reinforcement body. A horizontal flow path is formed inside a pair of protrusions facing each other among the plurality of protrusions to enable communication between the flow path of the reinforcing body and the porous metal layer of the unit cell. This horizontal flow path formed to face each other is rotated by 90 degrees in the adjacent frame, so that the hydrogen gas and oxygen gas generated from the hydrogen electrode and the oxygen electrode of the unit cell, respectively, are alternately converted to the hydrogen flow path or the oxygen flow path of the reinforcement body through independent flow paths. flow becomes possible. Of course, it is preferable for the neighboring gasket skeleton to be rotated by 90 degrees with respect to the central axis for convenience of manufacture or stability of the device.

According to Patent Document 1, in order to perform compression and storage of hydrogen/oxygen production by electrolysis, the electrolysis unit is disposed inside the housing filled with oxygen, and the hydrogen gas and oxygen gas produced are stored in a storage container of the gas storage unit disposed outside the housing. A part of the stored and produced oxygen gas fills the empty space inside the housing. The key to this method is to equalize the pressure of hydrogen gas and oxygen gas inside the device, and at the same time, balance the pressure of oxygen gas inside the housing. Since hydrogen-oxygen gas is produced in a quantitative volume ratio from water electrolysis, equalization of gas pressure can be easily achieved by adjusting the volume in the vessel occupied by these gases.

However, in this method, there is a possibility that a combustion reaction may occur when hydrogen and oxygen gas inside the water electrolysis unit are mixed due to a sudden leakage or when hydrogen gas inside the electrolysis unit is mixed with oxygen gas in the empty space inside the housing. The present invention proposes a method of filling most of the space inside the housing with a non-combustible liquid such as water in order to suppress the combustion reaction of hydrogen and oxygen gas, contacting the liquid surface, and filling the upper space of the housing with high-pressure oxygen gas. Therefore, the peripheral components such as the stack and the separator are immersed in a liquid such as water within the housing. Through the incompressible liquid, the pressure of oxygen gas is transferred to the outer wall of the stack as it is, and the pressures applied to the inside and outside of the stack can be equalized.

When hydrogen/oxygen gas is mixed due to rupture of components inside the stack, the aftereffect can be divided into two categories. The first case is a small leak. At this time, the power is cut off by the controller, so the production of any more gas is stopped. Therefore, the mixing degree is low, so that electricity cannot be generated by the combustion reaction of hydrogen/oxygen gas. The second case is a case in which the stack structure is momentarily ruptured due to an increase in gas pressure inside the stack, and a large amount of hydrogen/oxygen gas inside the stack is mixed or leaked out of the stack. In this case, a large amount of gas has already flowed out of the stack before the controller operates, and there is a possibility to create a mixture ratio that can generate power through a combustion reaction of hydrogen/oxygen gas. Therefore, the chemical stability of the electrolysis device is closely dependent on the preparedness for the second case. When the stack and the separator are placed in water, the hydrogen/oxygen mixed gas leaked from the stack is already mixed with water before being mixed with oxygen in the upper part of the water inside the container. However, it does not develop into an explosive reaction.

The next step is to solve the problem of gas purity. When the pressure of hydrogen and oxygen gas inside the water electrolysis device increases, the solubility of hydrogen and oxygen gas in the electrolyte solution also increases. For example, if the pressure of hydrogen and oxygen gas is 500 atmospheres, 0.78 g and 20 g of hydrogen and oxygen gas are dissolved in 1 liter of water, respectively. Therefore, in high-pressure electrolysis, mixing of the electrolyte/hydrogen gas mixture and the electrolyte/oxygen gas mixture should be minimized, and the use of an ion exchange resin membrane is preferable. If a porous membrane is used as a separation membrane, a method must be devised to remove the impurity gas generated by movement.

The water electrolysis device can be divided into an anion exchange resin separator system and a cation exchange resin separator system according to the use of the separator or the acidity of the electrolyte. It does not matter which system is used to explain the principle of the present invention, but alkaline solution electrolysis is selected as an example. In alkaline solution electrolysis, hydrogen and oxygen gas are generated by the following reaction, respectively.

At the hydrogen electrode, 4 H ₂ O + 4 e ^- → 2 H ₂ + 4 OH ^- (1)

At the oxygen electrode, 4 OH ^- → 2 H ₂ O + O ₂ + 4 e ^- (2)

The overall reaction is 2 H ₂ O → 2 H ₂ + O ₂ (3)

As the electrolysis proceeds, water is consumed in the hydrogen electrode, and half of the consumed amount is regenerated in the oxygen electrode. Hydroxide ions (OH ⁻ ) generated at the hydrogen electrode diffuse to the oxygen electrode through a separator such as an anion exchange membrane.

When a porous membrane is used as a separator instead of an anion exchange resin membrane in alkaline decomposition, it is impossible to completely block the transfer of hydrogen or oxygen gas through the membrane. Therefore, a method of removing the moved hydrogen or oxygen gas should be searched for with a certain degree of movement. In the present invention, a removal method through an electrochemical catalyst column was selected. This method is similar to the principle of electrochemical corrosion. The space on the side of the hydrogen electrode will be described as an example in the space on the side of the hydrogen electrode and the oxygen electrode with the separator as a boundary. The hydrogen/electrolyte mixture mixed with a small amount of oxygen that has migrated through the membrane leaves the stack and passes through the catalyst column as it flows to the gas separator. As the catalyst column, a high surface area nickel electrode coated with platinum or silver may be used. A trace amount of oxygen and a large amount of hydrogen on the surface of the column electrode are respectively

2 H ₂ + 4 OH ^- → 4 H ₂ O + 4 e ^- (4)

2 H ₂ O + O ₂ + 4 e ^- → 4 OH ^- (5)

The reaction produces water as a whole and oxygen is removed.

The overall reaction is 2 H ₂ + O ₂ → 2 H ₂ O (6)

The above reaction is the same as the hydrogen/oxygen fuel cell reaction, and since both reactions occur on the same surface, no electromotive force is generated and it can be regarded as a kind of corrosive reaction. Hydrogen is removed by the same reaction even in the space of the oxygen electrode where a small amount of hydrogen has moved. A trace amount of oxygen or hydrogen dissolved in hydrogen/electrolyte or oxygen/electrolyte exists in a molecular state, so it can be easily removed by reaction (4) and (5).

Other issues to be considered in the water electrolysis system are the water supply, the water level adjustment of the brackish water separator, and the circulation of the electrolyte. In water electrolysis, hydrogen gas and oxygen gas are separated from their electrolytes in each brackish water separator, and after purification and drying through each path, they are injected into a storage container, or purified and dried after storage. . In the case of high-pressure water cracking, the two electrolytes in which the gases are separated are always re-supplied to the stack through independent paths. The reason for circulating the electrolyte between the separator and the stack is to help equalize the internal temperature of the stack and to reduce the electrical resistance by rapidly removing gas bubbles generated from the electrode.

In water electrolysis, the electrolyte level of the hydrogen-oxygen separator depends on the pressure difference between the two gases. The pressure of a gas is determined by the volume allowed for the gas and the output per hour. Also, the water level of the brackish separator depends on the amount of water produced and consumed by the reactions (1) and (2). Therefore, in order to maintain the initial water level, the hydrogen electrode must supply water and the oxygen electrode must properly drain water. However, since a large amount of oxygen is dissolved in the electrolyte of the oxygen water separator under high pressure conditions, it is necessary to pay attention to its drainage. One method of drainage is to join the hydrogen gas/electrolyte mixture that circulates to the hydrogen separator through a discharge path when the water level in the oxygen separator exceeds the upper limit. The combined mixture passes through the electrochemical catalyst column to convert dissolved oxygen into water and enters the hydrogen degassing unit. Another method is to discharge the excess to the outside of the electrolysis section and discard it. In this case, the amount of water supplied to the hydrogen degassing separator should be doubled.

If hydrogen and oxygen are produced in an electrolysis quantitative ratio of 2:1, then in order to make the pressures of the two gases equivalent, the ratio of the volumes occupied by these gases in the stack must also be 2:1. However, it is not easy to maintain an accurate volume ratio inside the stack. Therefore, it is possible to adjust the volume by adding or draining water to the hydrogen gas area and the oxygen gas area inside the stack. The housing containing the stack and filled with water and high-pressure oxygen gas can act as a volume adjuster by draining the liquid inside if necessary.

Supply and drainage of water and circulation of electrolyte liquid in a high-pressure electrolyzer are not as simple as in a normal-pressure electrolyzer. In an environment where the pressure of a fluid of several hundred atmospheres exists, there is a limit to circulating the fluid by moving a mechanical means such as a piston with electrical power. In the high-pressure electrolysis device, the continuous increase in the pressure of hydrogen/oxygen gas as a function of time along with the application of power may be used as a driving force for fluid movement. The actuation of an on-off valve can induce a pressure differential between the fluid moving compartments, and a slight pressure differential before and after a means such as a piston facilitates the movement of the electrolyte.

The economics of the in-stack pressure equalization method for high-pressure hydrogen production/compression depends on the simplicity of the housing structure in which the stack is placed and filled with water/high-pressure oxygen gas. Components such as stacks of the device require periodic disassembly and regeneration after a certain period of time, so the housing must be stable to high pressure as well as simple to open and close.

The structure of the housing consists of two components that can be opened and closed, for example, an upper and a lower half. For example, the local stress applied to the joint groove of the bolt and the nut is very large because the nut boundary with the bottom of the lower half receives a downward force by the bottom and an upward force through the bolt. As the pressure of the gas and liquid inside the housing increases, the material for making the bolt and nut reaches its limit in overcoming high stress. If the structure is deformed so that the force to lift the upper half of the housing and the force to lower the lower half of the housing push each other at their joint surfaces, the local stress is relieved and the housing can maintain mechanical stability even at high internal pressure.

The greatest feature of the high-pressure hydrogen and oxygen gas production and storage device according to the present invention is that the gas production and compression are simultaneously achieved by an electrochemical method. Production is achieved by electrolysis of water and compression is achieved by electrochemical rather than mechanical compression. Therefore, in this method, the size of the entire device is significantly reduced compared to the existing method using by-product hydrogen or hydrogen produced by reforming fossil fuels. In addition, the mechanical stability of the gas separation membrane can be increased through pressure equalization of hydrogen gas and oxygen gas produced from water electrolysis, and local stress on the stack can be reduced through pressure equalization inside and outside the stack. In addition, there is an advantage in that the cost of the device can be very low by using a low-cost flexible electrode, a gas escape layer, and a low-cost porous separator. The biggest effect of reducing size and price is that it can accelerate the practical use of hydrogen charging stations.

1 is a view schematically showing the overall configuration of a hydrogen production compression storage device according to the present invention.

Figure 2 is a structural view of the housing containing the stack and auxiliary devices of the water electrolysis device therein.

Fig. 3a is a planar view of a tubular stiffener enclosing the stack outwardly;

3B is a perspective view of a reinforcement body;

3C is a perspective view of a gasket skeleton as a unit cell component;

FIG. 3D is a plan view showing a state in which the gasket skeleton of FIG. 3C is inserted into the inner space of the reinforcement body of FIG. 3A, wherein the hydrogen gas flow path is open;

FIG. 3E is a plan view showing a state in which the gasket skeleton of FIG. 3C is inserted into the inner space of the reinforcement body of FIG. 3A, and the oxygen gas flow path is open;

FIG. 4 is a cross-sectional view of a stack showing a connection between a hydrogen/electrolyte flow path formed in a reinforcement member and a stack unit cell; FIG.

5 is a view comprehensively showing an electrolyte supply to and a gas discharge path from the hydrogen and oxygen separator.

6A is an explanatory view of a pumpless circulator for supplying an electrolyte from a water separator to a stack;

6B is a graph showing the change with time of the gas pressure measured at each point in the fluid circulation path of a pumpless circulator;

Hereinafter, terms such as vertical, horizontal, and equilibrium are used while describing the present invention, but this is not used to limit the content of the present invention to only the case of mathematically perfect vertical, horizontal, and equilibrium.

In order to solve the above problems, the present invention shows a method of simultaneously producing and compressing hydrogen gas and oxygen gas by water electrolysis. When the pressure of hydrogen and oxygen gas rises, local stress is applied to the parts or internal parts that bind the high-pressure water electrolysis device (hereinafter referred to as "device"). Pressure balancing is important to reduce stress, and the following method is used.

Pressure equalization has two meanings. The first refers to the equilibrium between the hydrogen gas pressure and the oxygen gas pressure applied to both sides of the polymer membrane that separates the two electrodes of the unit cell inside the stack, which is the main component of the device. The second is to make the gas pressure inside the stack and the gas pressure outside the stack have the same value. In order to maintain the equilibrium of the first meaning, it is possible by adjusting the volume of the two containers according to the pressure measurement (monitoring) of the hydrogen storage container and the oxygen storage container. In order to maintain the equilibrium of the second meaning, the stack is placed inside the housing, which is a closed system, and the produced oxygen gas is introduced into the housing, which is mostly filled with water. At this time, as oxygen flows in, it becomes possible to adjust the space occupied by oxygen gas by drainage.

Hydrogen gas produced by electrolysis can be captured in a water storage vessel that supplies water to the device. The advantage of such collection is that hydrogen gas naturally occupies the empty space that is created when water is consumed by water electrolysis. Therefore, it is not necessary to separately provide storage containers for hydrogen and oxygen gas.

Most of the space inside the housing is filled with a non-flammable liquid such as water, and only about 10% of the total volume is filled with oxygen gas. Even if the stack and other components arranged inside the housing rupture due to the high-pressure gas, the risk of explosion is excluded because the hydrogen/oxygen gas is mixed with water once. And the water inside the housing plays an important role in equalizing the pressures of hydrogen gas and oxygen gas. Since the volume ratio of the two gases produced from water electrolysis maintains a quantitative ratio, the pressure of these gases is determined by the volume occupied by each gas. Therefore, it is possible to adjust the volume of oxygen gas inside the housing by discharging some of the water inside the housing or receiving it from an external water storage source. When the pressures of hydrogen gas and oxygen gas are equalized, naturally the pressures inside and outside the stack are also equalized.

When the pressure of hydrogen or oxygen gas increases during water electrolysis, the concentration of these gases dissolved in the electrolyte also increases. Therefore, in alkaline water electrolysis, the hydrogen electrode and oxygen electrode must be blocked with an anion exchange resin separator to minimize mixing of hydrogen gas/electrolyte and oxygen gas/electrolyte. In the case of using a porous membrane, it is necessary to remove the moved hydrogen or oxygen gas. Hydrogen gas/electrolyte and oxygen gas/electrolyte discharged from the stack are separated from hydrogen and oxygen gas in the hydrogen and oxygen separator, respectively, and the remaining electrolyte is re-introduced into the stack through an independent flow path. The separated oxygen gas fills the empty space inside the housing.

In alkaline water electrolysis, water is consumed at the hydrogen electrode and water is regenerated at the oxygen electrode. Water from the water supply part is supplied to the hydrogen separator through a valve connected to the bottom of the container. In addition, the upper empty space of the water supply unit is filled with high-pressure hydrogen gas. The water supply rate is determined by the current value supplied from the power source, and the fine adjustment is determined by the flow cross section of the valve. The water level of the brackish water separator for hydrogen is complexly dependent on the following factors. The water level is determined by the supply of water from the water storage source and the inflow of the electrolyte corresponding to the rise in the water level of the oxygen water separator. The above-mentioned input amount is determined by the electric current and the electrochemical reaction. Another factor that determines the separator water level is the gas pressure. The initial value of the water level can be maintained by equalization of the hydrogen-oxygen gas pressure. If the production rates of the two gases are constant, the water level can be maintained by adjusting the volume occupied by these gases in the device.

A schematic diagram of a high-pressure hydrogen production compression device based on the above principle has been described in FIG. 1 . In the illustration below, an alkaline electrolysis device in which OH ^- ions move through an anion separator is used as an example, but the same principle is applied to water electrolysis using a noble metal electrode and Nafion. The entire device 10 shown in FIG. 1 includes a housing 110 containing various components for hydrogen/oxygen production and compression, and a container 700 disposed outside the housing to serve as both high-pressure hydrogen storage and water storage. am. The housing 110 is also used as a storage container for high-pressure oxygen. Inside the housing, the hydrogen gas and oxygen gas separator 300 and the oxygen separator 400 for separating the stack 200, which are core elements of the water electrolysis unit, and the hydrogen gas and oxygen gas produced in the stack from the electrolyte are disposed.

The inside of the housing 110 is filled with water 150 , and the oxygen gas 152 generated by electrolysis fills the empty space generated by drainage through the lower valve 153 . That is, the lower valve 153 can control the pressure of the oxygen gas by adjusting the volume occupied by the oxygen gas as a drain control unit. The hydrogen gas 310 and the oxygen gas 410 separated from the

electrolytes

320 and 420 in the water separator are introduced into the hydrogen storage device 700 through the

respective discharge paths

303 and 403 and are stored or stored (308) in the housing. It is simultaneously introduced into the interior 152 and the oxygen storage device 800 and stored. Water used for electrolysis is supplied from the storage source 620 to the hydrogen water separator 300 through the valve 121 and the inflow path 122 . After the gas is discharged from the separator, the hydrogen electrolyte 320 and the oxygen electrolyte 420 are introduced into the stack 200 through

respective circuits

302 and 402 . A mixture of the hydrogen/oxygen gas generated in the stack and the electrolyte solution enters each water separator through the

respective flow passages

301 and 401 . At this time, before flowing into the separator, the mixture of hydrogen gas/electrolyte and oxygen gas/electrolyte passes through each electrochemical column 201 .

The inside of the electrochemical column 201 is filled with a high surface area catalyst coated with platinum-based noble metals (Pt, Pd, Ru, Ir), iron (Fe), cobalt (Co), silver (Ag), and the like. A sintered high surface area nickel electrode or carbon may be used as the catalyst. A small amount of oxygen or hydrogen/electrolyte mixture or oxygen/electrolyte mixture mixed with hydrogen that has moved through the separation membrane inside the stack passes through the catalyst column when it leaves the stack and flows to each degassing separator. A trace amount of hydrogen or oxygen dissolved in the electrolyte is converted into water by an electrochemical reaction as it passes through this catalyst column.

2 is a schematic cross-sectional view showing an embodiment of the structure of the housing. In FIG. 2 , a stack and other components 202 among various components positioned inside the housing are illustrated in a simplified manner. As other components, there may be a water separator or an inversion chemical column as described with reference to FIG. 1 .

The housing in which the empty space inside is filled with water/high-pressure oxygen gas includes two elements, an upper housing and a lower housing that can be opened and closed. When the internal pressure increases, these two elements have a structure in which the force acts in the direction of strengthening the bonding force rather than the force in the direction of separation.

That is, an annular flange 112 extending in a radial direction is formed on the lower side of the upper housing, and a U-shaped annular joint 114 having a radially extended “C”-shaped cross section on the upper side of the lower housing. ) is formed. An "L"-shaped flange is formed on the upper part of the lower housing to form a U-shaped annular joint 114, and an annular pressing part is fixed on the upper part of the "L"-shaped flange using a bolt 116 and a nut 118. method can be used.

In this case, when the pressure inside the housing increases, a force acts in a direction in which the upper housing and the lower housing move away from each other. This force strengthens the joint between the flange upper surface of the upper housing and the lower part of the annular pressing part. direction will work. That is, the structural stability of the housing can be improved by using the pressure of the high-pressure oxygen gas 152 inside the housing to strengthen the airtightness of the bonding surface. Here, a member such as a gasket for sealing may be used between the L-shaped flange and the annular pressing portion and between the annular pressing portion and the annular flange, respectively, and the number, size, and spacing thereof may be adjusted as necessary.

Power to the stack is supplied from a DC power supply 205 outside the housing.

Hydrogen gas 310 flowing out from the hydrogen container water separator 300 located inside the housing is stored in the high-pressure hydrogen and water storage container 700, and when using the hydrogen gas 308 stored in the high-pressure hydrogen and water storage container It is made to pass through the purification column 312 and the drying column 314 . Oxygen gas 152 inside the housing or oxygen in the oxygen storage 800 outside the housing also passes through the purification column 412 and the drying column 414 when in use. The oxygen storage 800 serves only to help when determining the initial oxygen space, and may be excluded from the device.

The vertical force pressing the upper and lower surfaces of the cylindrical stack placed inside the housing filled with high-pressure gas is effective to offset the vertical force generated by the gas generation inside the stack. However, the radial force (lateral force, radial force in the case of a cylindrical flow path) applied to the inner wall of the flow path formed vertically in the vertical direction of the stack is a horizontal force, and suppressing this force is also important to maintain the structural stability of the stack. Do.

In the present invention, a reinforcement unitary body surrounding the stack is used as a means to withstand the force in the horizontal direction. When the stack is cylindrical, the reinforcing body is made in a tubular shape to adhere to the outside of the stack to support the force acting in the horizontal direction inside the stack. The reinforcing body is a unitary polymer material, and it is preferable to take a form in which the stack is disposed so as to be in close contact with the empty space therein. A reinforcing body flow path 272 is formed in the reinforcing body, so that the flow path passing through the cylindrical axial direction and the unit cells of the stack communicate with each other. The gasket skeleton used in response to each unit cell of the stack plays an important role in making such a connection path.

3A and 3B are respectively a plan view and a perspective view of a tubular reinforcement that surrounds the stack. 3C is a perspective view of a gasket frame, and FIG. 3D is a plan view showing a state in which the gasket frame is inserted into the inner space of the reinforcement body. is connected to, and a view showing a state in which the oxygen entry channel and the oxygen release channel are closed by the channel closing protrusion is shown, and FIG. , the oxygen entry flow path and the oxygen discharge flow path are respectively connected to the reinforcement flow path, and the hydrogen entry flow path and the hydrogen discharge flow path are closed by the flow path closing protrusion.

The internal cylindrical hollow space 242 of the reinforcing body 240 may be disposed in such a way that a cylindrical stack is also pushed. At this time, the protrusion of the gasket skeleton, which is a component of the stack unit cell, is disposed in a form to be inserted into the valley-shaped

spaces

255 and 265 formed parallel to the cylindrical axis on the side of the inner space of the reinforcement body, so that the two elements, that is, the reinforcement body It helps the tight bonding of the stack and the stack. At this time, if a liquid adhesive is applied to the inner wall of the hollow part of the reinforcing body and the side of the gasket skeleton, it can dry and fill the empty space between the two elements to help adhere. Of the four flow passages penetrating in the cylindrical axial direction of the reinforcement body, two opposite flow passages are hydrogen passages (hydrogen entry passage and hydrogen discharge passage) 251 and 252, the inflow and outflow of hydrogen/electrolyte into the unit cell, and the remaining two flow passages are As oxygen flow paths (oxygen inlet flow path and oxygen discharge flow path) 261 and 262, they are used as inflow and outflow passages of oxygen/electrolyte to the unit cell.

On the other hand, the connection between the hydrogen flow path of the reinforcement body and the unit cell is performed by maintaining the hydrogen connection path 255 of the valley-type space in an open state by the gasket framework flow path 271 formed in the protrusion of the gasket framework, and oxygen of the reinforcement body The connection between the flow path and the unit cell is achieved by maintaining the oxygen connection path 265 of the valley-shaped space in an open state by the gasket framework flow path 271 formed on the protrusion of the gasket framework. (The

reference numbers

255 and 265 are used to refer to the entire valley-shaped space formed in the reinforcement, and the

reference numbers

255 and 265 are used to refer to the hydrogen or oxygen connection passages that are part of it.) A plurality of bolt fastening holes 243 may be formed and used to bind unit cells of a stack disposed inside the reinforcing body. Accordingly, the inner surfaces of the two covers covering the upper and lower portions of the reinforcing body come into contact with the outer surfaces of the uppermost and lowermost metal plates of the stack, respectively, so that the force applied when the bolts are fastened is transmitted in a form of compressing the unit cells.

The gasket skeleton 270 is formed with two passage closing protrusions 273 and two passage connecting protrusions 271 protruding outward. The flow path closing protrusion 273 closes the horizontal connection path (hydrogen connection path or oxygen connection path) 255 or 265 of the reinforcement body 240 , and the flow path connection projection 271 is the horizontal direction of the reinforcement body 240 . Each unit cell of the stack disposed in the hollow part of the reinforcing body by forming a gasket skeleton flow path 272 while having an outer shape corresponding to the cross-sectional shape of the connection path (hydrogen connection path or oxygen connection path) 255 or 265; The

flow paths

251 , 252 , 261 , or 262 formed in the reinforcement body 240 may communicate with each other. Through the

connection path

255 or 265 of the reinforcement body 240 to the hydrogen electrode 220 or the oxygen electrode 210 of each unit cell, or from the hydrogen electrode 220 or the oxygen electrode 210 to the reinforcement body 240 In order to make the gas/electrolyte flow to the

connection path

255 or 265 , the gasket skeleton 270 is used to contact the hydrogen electrode or the oxygen electrode of the unit cell, respectively. That is, the shape shown in FIG. 3D is such that the vertical hydrogen entry flow path 251 and the hydrogen discharge flow path 252 formed in the reinforcement body are connected to the unit cell by the gasket skeleton flow path 272, and the shape shown in FIG. 3E (The shape shown in FIG. 3C is rotated by 90 degrees), a method in which the oxygen inlet flow path 261 and the oxygen discharge flow path 262 are connected to the unit cell by the gasket skeleton flow path 272 may be used.

On the other hand, in the ring-shaped cross section of the reinforcing body having an inner hollow portion, the ring thickness (t in FIG. 3A ) is formed to be 10% to 100% of the inner diameter of the hollow portion (d in FIG. 3A ) and a cross-sectional area of the horizontal connection path in the reinforcing body into which the gasket skeleton protrusion is inserted is 2% to 200% of the cross-sectional area of the vertical hydrogen inlet channel, hydrogen outlet channel, oxygen inlet channel, and oxygen outlet channel.

The reason that the gasket skeleton is not in close contact with the hollow part of the reinforcing body in FIGS. 3D and 3E is to show that the gasket skeleton is a separate member from the reinforcing body skeleton in the drawing, and the gasket skeleton is the gasket skeleton flow path. Although it is shown as being divided into two parts with the skeletal flow path between It is not designed to be split into two parts.

4 is a view showing that the

hydrogen passages

251 and 252 and the hydrogen connection passage 255 of the reinforcement body and the gasket skeleton flow passage 272 communicate with the unit cell, and is a cross-sectional view of the unit cell coupled to the reinforcement member. is shown. That is, FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3D in a state in which the stack is coupled to the reinforcing body. As shown in FIG. 4 , in the unit cell, with a separator 230 disposed between the gasket skeleton of the form shown in FIG. 3d and the gasket skeleton of the form shown in FIG. 3c therebetween, an oxygen electrode 210 is below. , a hydrogen electrode 220 is disposed on it, and a porous gas diffusion layer 232 and a bipolar distribution board 234 are stacked in contact with each electrode. Hydrogen gas/electrolyte is introduced into the unit cell through the hydrogen inlet passage 251 formed in the vertical direction formed in the reinforcement body, the hydrogen inlet connection passage 255 formed in the horizontal direction, and the gasket skeleton passage 272, and then in the horizontal direction. It is discharged through the formed gasket skeleton flow path, the hydrogen discharge connection path 255 in the horizontal direction formed in the reinforcing body, and the hydrogen discharge flow path 252 formed in the vertical direction. The flow path connecting protrusion 271 and the flow path closing protrusion 273 formed on the edge of the gasket skeleton 270 of the hydrogen electrode have a shape corresponding to the cross-sectional shape (rectangular in the drawing) of the connecting

paths

255 and 265 formed in the reinforcing body. is made That is, the flow path closing protrusion 273 is fitted to the connection path 265 to completely close the connection path 265 , and the flow path connection protrusion 271 is the gasket skeleton flow path 271 except for a portion. The connection path 255 is completely in close contact with the wall.

In order to equalize the hydrogen gas and oxygen gas pressures of the device 10 of the present invention, the electrolyte level must first be adjusted. The drop in the hydrogen brackish water level due to electrolysis is covered by the supply of water from the water storage source and the transfer of excess from the oxygen brackish separator. As shown in FIG. 5 , when the water level of the oxygen water separator 400 exceeds the upper limit, the excess is combined with hydrogen/electrolyte through the discharge path 405 and is moved to the hydrogen water separator 300 . At this time, the combined mixture passes through the electrochemical catalyst column 201 to remove oxygen dissolved in the oxygen electrolyte and then flows into the hydrogen water separator 300 . An excess of the oxygen separator may be discharged to the outside of the housing through the drain 406 .

In order to equalize the pressure, it is necessary to adjust the volume occupied by the gas in the device along with the water level in the separator. To do this, first, the initial volume to be occupied by hydrogen and oxygen gas should be determined at the start of electrolysis, and the ratio should be such that oxygen is less than 50% of the hydrogen volume. For this purpose, before filling the water reservoir and housing with water, the air inside the device is pumped out, leaving only the initial space for gas to flow when filling with water. The initial spatialization of hydrogen and oxygen determines the final pressures of these gases. When the pressure of hydrogen gas and oxygen gas inside the device to be measured (monitor) is different as the electrolysis proceeds, the volume occupied by each gas is adjusted. For this purpose, in this device, it is easier to manipulate the volume of oxygen gas than hydrogen gas. The reason is that oxygen gas flows in and the volume inside the housing occupied is adjustable by a multiple of water 150 .

The electrolyte of the device circulates between the hydrogen separator and the stack and between the oxygen separator and the stack through independent flow paths. 6a shows the principle of circulating the electrolyte between the hydrogen separator and the stack without using a pump. The circulation between the oxygen degasser and the stack follows the same principle. In order to obtain a circulating force, a bypass passage is made so that a part of the hydrogen gas leaving the separator can flow in the stack direction. A high pressure gas chamber 330 (high pressure chamber) is arranged as a small hydrogen gas temporary storage in the passage, and a small electrolyte supply container 335 is arranged. A piston 336 is installed inside the electrolyte supply container, and the upper half of the container in contact with it is filled with the hydrogen electrolyte 320 and the lower half with the high-pressure hydrogen gas 311 supplied through the branch passage. Through the opening and closing of a plurality of valves installed in the passage, the hydrogen gas pressure inside the high-pressure gas chamber 330 is momentarily higher than the pressure inside the stack, and the piston is moved upward with the gas pressure to supply the electrolyte to the stack. Therefore, it is important to induce a pressure differential between each point in the circulation path, which can be achieved using multiple on-off valves. First, the valve 341 located in the path 303 leading to the main hydrogen storage 700 is closed, and the valve 342 leading to the high-pressure gas chamber 330 is opened to increase the pressure of the high-pressure gas chamber 330 . When the electrolyte is pushed out, the valve 341 is opened again. At this time, the mixture of hydrogen gas and electrolyte is introduced into the hydrogen water separator 300 after passing through the electrochemical catalyst column 201 along the discharge path 301 . A cycle consists of three phases, each of which is

Step 1: Hydrogen Filling of Temporary Hydrogen Reservoir

Step 2: Supply of electrolyte to the stack by using a piston

Step 3: Recharge the electrolyte in the electrolyte supply container and move the piston downward

and the opening and closing of multiple valves according to this step are summarized in Table 1.

[Table 1]

valve 341 342 343 344 345

step 1 c o c o o

step 2 o c o c o

step 3 o c o o o

o: open c: close

A profile showing the gas pressure measured at two points in the hydrogen gas path as a function of time or as a function of period and step is shown in FIG. 6B .

In describing the present invention so far, the embodiment shown in the drawings has been described with reference to, but this is merely an example, and that various modifications and equivalent other embodiments are possible therefrom by those of ordinary skill in the art. will understand the point. Accordingly, it is obvious that the true technical protection scope of the present invention is determined by the technical spirit of the appended claims.

Claims

a water electrolysis unit in which a stack in which a plurality of unit cells including an oxygen electrode and a hydrogen electrode are stacked is disposed therein to produce and compress hydrogen required for hydrogen charging at a place of use by electrolysis;

a hydrogen gas storage container for storing the hydrogen gas produced by the water electrolysis unit; and

It includes a housing that blocks the external and internal space as the water electrolysis unit is installed in the internal space,

The water electrolysis unit is disposed in the housing in a state submerged in a non-combustible liquid,

A part of the oxygen gas produced by the water electrolysis unit fills the space inside the housing, and the pressure maintains equilibrium with the hydrogen gas pressure of the hydrogen gas storage container while producing, compressing, and storing hydrogen and oxygen gas. High-pressure hydrogen and oxygen gas production and storage device using cracking.
The method of claim 1,

The stack of the water electrolysis unit is placed in the hollow part inside the tubular reinforcement made of a polymer material to structurally reinforce the outer periphery, and then placed in the housing,

The reinforcing body is formed as a tube-shaped body so that the inner hollow part accommodates the stack, is spaced apart from each other around the hollow part, is connected to the hollow part, and extends in a vertical direction: a hydrogen inlet channel, a hydrogen discharge channel, an oxygen inlet channel, and An oxygen discharge flow path is formed, and a horizontal connection path through which the hydrogen entry flow path, the hydrogen discharge flow path, the oxygen inlet flow path and the oxygen discharge flow path can be connected to the stack is formed,

In each of the plurality of unit cells included in the stack, an oxygen electrode and a hydrogen electrode are disposed below, and a porous gas diffusion layer and a bipolar distribution board are disposed in contact with each electrode with a separator disposed in the central portion therebetween, a hydrogen electrode; It includes a ring-shaped gasket skeleton that surrounds the oxygen electrode and the porous gas diffusion layers from the outside and is in close contact with the distribution board,

The ring-shaped gasket skeleton surrounds the hydrogen electrode located on one side of the separator and the porous gas diffusion layer and is in close contact with the bipolar distribution board, and the oxygen electrode located on the other side of the separator, the porous gas diffusion layer, and a portion in close contact with the bipolar distribution board, It has four protrusions that protrude outward and are inserted into the horizontal connection path formed in the horizontal direction of the reinforcing body, two of the protrusions close the horizontal connection path, and the remaining two protrusions have a gasket frame flow path. is formed to enable fluid movement through the horizontal connection path, and the gasket skeleton enclosing the oxygen electrode and the gasket skeleton enclosing the hydrogen electrode have different protrusions on which the gasket skeleton passage is formed, so that the gasket skeleton passage on one side communicates with the hydrogen electrode, , the gasket skeleton on the other side communicates with the oxygen electrode,

High-pressure hydrogen and oxygen gas using water electrolysis, characterized in that the inner wall forming the hollow portion of the reinforcing body and the lateral outer wall of the gasket skeleton, which is a component of the stack disposed in the hollow portion of the reinforcing body, are in close contact with each other production and storage devices.
3. The method of claim 2,

A gasket skeleton flow path is formed in two of the four protrusions of the gasket skeleton (gasket skeleton for hydrogen electrode) surrounding the hydrogen electrode, and is connected to the hydrogen entry passage and hydrogen emission passage, respectively, and the gasket skeleton (gasket for oxygen electrode) surrounding the oxygen electrode. In two of the four protrusions of the skeleton), a gasket skeleton flow path is formed and is connected to the oxygen inlet passage and oxygen release passage, respectively. High-pressure hydrogen and oxygen gas production and storage device using water electrolysis, characterized in that it is rotated 90 degrees to each other.
3. The method of claim 2,

In the cross section of the ring-shaped shape of the reinforcing body having an inner hollow portion, the ring thickness is formed to be 10% to 100% of the inner diameter of the hollow portion,

The cross-sectional area of the horizontal connection path of the reinforcing body into which the gasket skeleton protrusion is inserted is 2% to 200% of the cross-sectional area of the vertical hydrogen entry flow path, hydrogen discharge flow path, oxygen inlet flow path, and oxygen discharge flow path,

The outer shape of the protrusion corresponds to the cross-sectional shape of the horizontal connection flow path and closes the protrusion while closely adhering to the connection flow path, except for the reinforcing body flow path portion,

A liquid contacting agent is used to adhere to the contact surface between the inner wall of the reinforcing body and the outer wall of the side of the unit cell,

High-pressure hydrogen and oxygen gas production and storage device using water electrolysis, characterized in that the vertical adjacent unit cell components are closely contacted by a bolt through a bolt fastening hole formed to penetrate parallel to the hollow part of the reinforcement body .
3. The method of claim 2,

The separator disposed between the plurality of unit cells to separate the hydrogen electrode and the oxygen electrode of an adjacent unit cell is a separator selected from the group consisting of a cation exchange resin separator, an anion exchange resin separator, or a porous separator. Water, characterized in that High-pressure hydrogen and oxygen gas production and storage device using electrolysis.
3. The method of claim 2,

The separator is a porous polymer separator,

An electrochemical catalyst column is disposed on the path in which the mixture of hydrogen gas and electrolyte produced in the hydrogen electrode and the mixture of oxygen gas and electrolyte produced in the oxygen electrode move to each water separator, and a trace amount of oxygen moving through the separation membrane I remove hydrogen,

A high surface area catalyst electrode is disposed inside the electrochemical catalyst column, and the high surface area catalyst electrode is made of one or more materials selected from the group consisting of nickel (Ni), titanium (Ti) and carbon, and the high surface area catalyst At least one metal selected from the group of metals including platinum-based noble metals (Pt, Pd, Ir, Ru), iron (Fe), cobalt (Co) and silver (Ag) is coated on the electrode surface,

High-pressure hydrogen gas production and storage device using water electrolysis, characterized in that the oxidation reaction of hydrogen and the reduction reaction of oxygen occur simultaneously on the surface of the high surface area catalyst electrode to produce water, and oxygen or hydrogen, which is an impurity, is removed.
7. The method of claim 6,

Further comprising a water supply unit for supplying water consumed in the hydrogen electrode together with the progress of electrolysis in the water electrolysis unit,

The empty space caused by the drainage in the water supply part is filled with hydrogen gas produced from electrolysis,

When the water level in the oxygen separator exceeds the upper limit due to the water generated at the oxygen electrode along with the progress of electrolysis in the water electrolysis section, the excess is discharged to the outside of the water electrolysis section or moved to the hydrogen water separator,

The excess discharged from the oxygen water separator is mixed with a mixture of hydrogen gas and electrolyte discharged from the stack formed by stacking unit cells, and then passes through an electrochemical catalyst column and flows into the hydrogen water separator. Water electrolysis characterized in that High-pressure hydrogen gas production and storage device using
8. The method of claim 6 or 7,

The hydrogen/electrolyte solution generated from the stack and discharged to the hydrogen discharge passage passes through an electrochemical catalyst column for hydrogen and a hydrogen water separator, and a hydrogen high pressure gas chamber connected so that hydrogen gas can be introduced at the outlet of the hydrogen water separator ;

The oxygen/electrolyte solution generated from the stack and discharged to the oxygen discharge passage passes through an electrochemical catalyst column for oxygen and a gas-water separator for oxygen, and is connected to an oxygen high-pressure gas chamber through which oxygen gas can be introduced at the outlet of the oxygen separator. ; and

The interior is separated into two spaces by a piston, one side of the space is connected to the hydrogen high-pressure gas chamber or the oxygen high-pressure gas chamber, and the other side is connected so that the electrolyte is supplied from the hydrogen gas-water separator or the oxygen gas-water separator. and the electrolyte supplied from the hydrogen or oxygen gas-water separator by the pressure supplied from the hydrogen or oxygen high-pressure gas chamber is supplied into the stack through the hydrogen ingress passage or oxygen ingress passage of the reinforcement body. High-pressure hydrogen and oxygen gas production and storage device using water electrolysis, characterized in that it further comprises an electrolyte supply container.
The method of claim 1,

The space into which the hydrogen gas and oxygen gas generated after the start of electrolysis in the entire device will be introduced is less than 50% of the space where the oxygen gas will be introduced,

The space where hydrogen gas flows includes a space where water from the water storage is drained,

The space into which the oxygen gas is introduced includes a space formed by draining the water filling the inside of the housing,

High-pressure hydrogen and oxygen using water electrolysis, characterized in that the housing further comprises a drainage control unit for adjusting the volume of the oxygen gas space by draining the water inside the housing so as to equally control the pressures of the oxygen gas and the hydrogen gas Gas production and storage devices.
The method of claim 1,

The housing for accommodating the stack formed by stacking unit cells includes a lower housing and an upper housing,

The upper housing has a hollow part open only on one side, and a flange extending outwardly along the periphery of the open part is formed,

The lower housing is formed with a hollow part with only one side open, and an 'L'-shaped flange for accommodating the flange of the upper housing as extending outward along the periphery of the open part is formed,

Further comprising a pressing part fixed while pressing the flange toward the 'L'-shaped flange,

High-pressure hydrogen by water electrolysis, characterized in that airtightness between the pressing part and the flange is strengthened when the pressure in the hollow part inside the housing is increased by fastening the 'L'-shaped flange and the pressing part with a bolt Oxygen gas production and storage devices.