Hydrogen production cell and hydrogen production method using hydrogen production cell

Abstract

To provide a hydrogen production cell of which a thickness per cell is reduced as compared with a conventional one.SOLUTION: A hydrogen side current collector 12 and an oxygen side current collector 13 are arranged on both sides of an electrolyte membrane 11. A separator 14 with a flat surface is arranged outside the hydrogen side current collector 12. A flow passage forming plate 15 and a separator 16 are arranged outside the oxygen side current collector 13. Since a flow passage dedicated for collecting water and a hydrogen gas generated when electrolysis is performed is not formed between the hydrogen side current collector 12 and the separator 16, the thickness of the cell itself can be reduced. These reaction fluids generated during the electrolysis are discharged from the inside of the hydrogen side current collector 12.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a hydrogen production cell and a hydrogen production method using the same.

Background Art

[0002] Conventionally, an oxygen-side current collector and a hydrogen-side current collector are arranged on both sides of a solid polymer electrolyte having an electrode catalyst layer formed on both sides, and a separator called a separator is arranged outside each of the oxygen-side current collector and the hydrogen-side current collector. A hydrogen production cell has been proposed that has a configuration in which the oxygen-side current collector and the hydrogen-side current collector are sandwiched between adjacent cells and partitioned by a sheet-like separator (Patent Document 1).

[0003] In such a case, in order to form dedicated flow paths for the reaction fluids generated by electrolysis between the separator and the oxygen-side current collector and the hydrogen-side current collector, a flow path forming plate having irregularities on its surface is provided. Further, without separately providing this flow path forming plate, irregularities for forming a dedicated flow path for the reaction fluid are also formed on the surfaces of the separator on the side of each current collector.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, as described above, when a flow path forming plate having irregularities for forming a flow path for the reaction fluid is provided between the oxygen-side current collector, the hydrogen-side current collector and the separator, the thickness of the water hydrogen production cell increases. The same applies when irregularities for forming a flow path for the reaction fluid are formed on the surface of the separator.

[0006] This type of hydrogen production cell is used in a state where dozens or more of them are stacked to form a cell stack. However, if there are uneven flow path forming plates that form the flow paths of the reaction fluid as described above, and separators with uneven surfaces, even if the thickness is about 1 mm, if it is a cell stack with dozens or more cells stacked, as a whole, it will occupy a space of several centimeters to dozens of centimeters in the thickness direction. Therefore, it is desired to make the hydrogen production cell itself more compact.

[0007] The present invention has been made in view of such a point, and aims to solve the above problems by realizing a structure of a hydrogen production cell that can reduce the thickness per cell compared to the prior art.

Means for Solving the Problems

[0008] To achieve the above object, the present invention provides a hydrogen production cell for producing hydrogen by water electrolysis, which has an oxygen-side current collector and a hydrogen-side current collector arranged on both sides of a solid polymer electrolyte having an electrode catalyst layer formed on both sides, and a separator arranged outside each of the oxygen-side current collector and the hydrogen-side current collector, and having a configuration in which the oxygen-side current collector and the hydrogen-side current collector are sandwiched, the surface of the separator arranged outside the hydrogen-side current collector on the hydrogen-side current collector side is flat, and no dedicated flow path for recovering the reaction fluid generated during electrolysis is formed between the separator arranged outside the hydrogen-side current collector and the hydrogen-side current collector.

[0009] According to the inventor, the hydrogen-side current collector used in this type of hydrogen production cell has a large number of voids that are organically connected inside. Therefore, by appropriately ensuring the porosity of the hydrogen-side current collector, without forming a special dedicated flow path for the reaction fluid on the outside as in the prior art, it has been newly found that hydrogen gas and water generated during electrolysis can pass through the voids inside the hydrogen-side current collector, be discharged from the hydrogen-side current collector, and be recovered. Therefore, it is not necessary to provide a separator having unevenness for forming a flow path or the like as in the prior art outside the hydrogen-side current collector. Therefore, the thickness per cell can be reduced compared to the prior art.

[0010] The porosity of the hydrogen-side current collector is preferably 50% to 99%. Since the reaction fluid is discharged and recovered through the voids inside the hydrogen-side current collector, it is advisable to use a hydrogen-side current collector having a porosity within this range.

[0011] The recovery parts for hydrogen gas and water generated from the hydrogen-side current collector may be respectively formed on a pair of opposite side parts of the hydrogen-side current collector. In such a case, a plurality of the recovery parts may be respectively formed on the opposite side parts. By forming a plurality of them, the recovery efficiency can be enhanced.

[0012] The hydrogen-side current collector has a shape with a long side part and a short side part, and preferably, the recovery parts are respectively formed on the opposing long side part sides. Thereby, the pressure resistance when moving inside the hydrogen-side current collector can be reduced, and recovery can be performed promptly.

[0013] From another perspective, a hydrogen production method using the above-described hydrogen production cell, characterized in that a voltage is applied between the oxygen-side current collector and the hydrogen-side current collector to generate hydrogen gas from the hydrogen-side current collector, can also be proposed as an invention.

Advantages of the Invention

[0014] According to the present invention, the thickness per cell can be reduced compared to the prior art. Also, the number of components constituting the cell can be decreased, and the cost can be kept low. Furthermore, as will be described later, it is possible to improve the performance of the cell itself and extend the life of the cell compared to the prior art.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0016] Hereinafter, embodiments will be described. FIG. 1 shows an outline of the system of a hydrogen production apparatus 1 incorporating a hydrogen production cell according to an embodiment. This hydrogen production apparatus 1 has a hydrogen production cell stack 4 configured by vertically standing a solid polymer type hydrogen production cell 10 shown in FIGS. 2 to 4 described later in a vertical direction, connecting and stacking several tens to several hundreds of them in series in a horizontal direction, and sandwiching them with end plates 2 and 3 from both sides.

[0017] Pure water, for example, which is raw material water, is supplied to the pure water inlet port P1 of the hydrogen production cell stack 4. Specifically, raw material water (pure water) is supplied from a tank 21 having a gas-liquid separation function on the oxygen side to the pure water inlet port P1 which is the raw material water inlet of the hydrogen production cell stack 4, and a water electrolysis operation (hydrogen production operation) is performed.

[0018] More specifically, a pipe 22 is connected between the bottom of the tank 21 and the pure water inlet port P1 of the hydrogen production cell stack 4. And pure water as raw material water is supplied from the tank 21 to the pure water inlet port P1 of the hydrogen production cell stack 4 by a pump 23 provided in the pipe 22. A check valve 24 is provided on the downstream side of the pump 23 in the pipe 22, and further on the downstream side thereof, a pressure gauge 25 for measuring the pressure in the pipe 22 is provided. The pure water inlet port P1 communicates with a communication port (details will be described later) in each of the hydrogen production cells 10.

[0019] In the pipe 22, on the downstream side of the pump 23, a return pipe 26 for returning a part of the water flowing in the pipe 22 to the tank 21 is connected. A flow rate regulating valve V1, a heat exchanger 27, an ion exchange resin tower 28, and a filter 29 are provided in the return pipe 26. By treating the return water through these devices, the water quality of the water in the tank 21 is maintained. A liquid level sensor 21a for detecting the water level in the tank is provided in the tank 21. Also, based on the signal from the liquid level sensor 21a in the tank 21, pure water as raw material water is appropriately replenished from an external pure water supply source (not shown) through the pipe 30. Further, the oxygen gas staying in the gas layer part in the tank 21 is discharged to the outside of the system through the pipe 33 or transferred to an external customer.

[0020] The raw material water supplied from the pure water inlet port P1 to the hydrogen production cell stack 4 through the pipe 22 is electrolyzed in the hydrogen production cell stack 4, and oxygen and the water that has not been decomposed are returned to the tank 21 through the pipe 31 from the pure water outlet port P2 serving as the oxygen side outlet, and are subjected to gas-liquid separation in the tank 21. A pressure gauge 32 for measuring the pressure in the pipe 31 and a solenoid valve V2 are provided in the pipe 31. Note that the check valve 24, the pump 23, the pressure gauge 32, and the solenoid valve V2 may not be provided. The pure water outlet port P2 communicates with a communication port (not shown) in the hydrogen production cell 10.

[0021] Pipes 41 are connected to the hydrogen outlet ports P3 and P4 serving as the hydrogen side outlets of the hydrogen production cell stack 4, and this pipe 41 leads to a tank 42 having a gas-liquid separation function on the hydrogen side. The hydrogen outlet ports P3 and P4 communicate with a communication port (not shown) in the hydrogen production cell 10.

[0022] A pipe 43 is connected between the tank 42 and the gas layer part of the tank 21 (the part above the liquid level of the water stored in the tank, and the part that the liquid level does not reach even if the stored liquid level rises). A solenoid valve V3 and a valve V4 are provided in the pipe 43. A liquid level sensor 42a for detecting the water level in the tank is provided in the tank 42.

[0023] Hydrogen generated by water electrolysis is sent, together with accompanying water, to the tank 42 through the pipe 41 and is gas-liquid separated inside the tank 42. The hydrogen gas after being gas-liquid separated in the tank 42 is sent through the pipe 44, for example, to the demand side or a hydrogen storage tank (high-pressure container, not shown). A back-pressure valve V5 is provided in the pipe 44, and a discharge pipe 45 is connected to the upstream side of the back-pressure valve V5 in the pipe 44, and a solenoid valve V6 is provided in the discharge pipe 45.

[0024] And a DC power source 5 is connected to the hydrogen production cell stack 4, and the pure water for electrolysis supplied from the pure water inlet port P1 is electrolyzed into hydrogen ions and oxygen ions according to the output thereof. Among them, the oxygen ions become oxygen molecules on the catalyst in the hydrogen production cell 10 and are discharged outside the cell from the pure water outlet port P2 together with the pure water as described above. On the other hand, the hydrogen ions generated by electrolysis move to the hydrogen side in the hydrogen production cell 10 along with the accompanying water, become hydrogen molecules on the hydrogen-side catalyst, and are discharged outside the cell from the hydrogen outlet ports P3 and P4.

[0025] Next, the hydrogen production cell 10 according to the embodiment will be described. As shown in FIGS. 2 to 4, this hydrogen production cell 10 has a configuration in which an electrolyte membrane 11, which is a solid polymer electrolyte, is sandwiched between a hydrogen-side current collector 12 and an oxygen-side current collector 13. The electrolyte membrane 11 has catalysts 11b and 11c on both surface sides of the solid polymer membrane 11a.

[0026] On the outside of the hydrogen-side current collector 12, a separator 14, which is a separator, is arranged. As the material of the hydrogen-side current collector 12, for example, carbon paper, carbon non-woven fabric, etc. are used, and a large number of organically connected voids are formed inside the hydrogen-side current collector 12. In this example, a hydrogen-side current collector 12 with a porosity of 50% or more is used. The surface of the hydrogen-side current collector 12 in the separator 14 is formed flat. The flatness here is not necessarily limited to being completely flat. Between the hydrogen-side current collector 12 and the separator 14, grooves and minute irregularities may be formed to such an extent that a dedicated flow path for the reaction fluid is not formed. However, the closer it is to being flat, the more the effects of the present invention can be obtained by uniform pressure contact over the entire electrode surface as described later.

[0027] The material of the oxygen-side current collector 13 is composed of a porous body of titanium having a predetermined rigidity, such as a sintered non-woven fabric of titanium fibers or a sintered metal of titanium. And on the outside of the oxygen-side current collector 13, a flow path forming plate 15 is arranged. On the outside of the flow path forming plate 15, a separator 16, which is a separator, is arranged. The flow path forming plate 15 is made of a material such as an embossed plate, a mesh, or a punching metal in which a large number of irregularities 15a are formed on the surface. As a result, a dedicated flow path 15b for the reaction fluid through which the fluid can flow in both the vertical and horizontal directions is formed between the oxygen-side current collector 13 and the flow path forming plate 15. Note that the flow path forming plate 15 and the separator 16 may be integrally formed. That is, instead of using the flow path forming plate 15, a separator known in the art in which irregularities for forming a reaction flow path are formed over the entire surface on one side surface may be used.

[0028] As shown in FIG. 2, the electrolyte membrane 11, the hydrogen-side current collector 12, the oxygen-side current collector 13, the separator 14, the flow path forming plate 15, and the separator 16 that constitute the hydrogen production cell 10 all have a horizontally long rectangular shape. And in each component that constitutes the hydrogen production cell 10, that is, the electrolyte membrane 11, the hydrogen-side current collector 12, the oxygen-side current collector 13, the separator 14, the flow path forming plate 15, and the separator 16, communication ports described below are all formed.

[0029] That is, communication ports 11d to 11g are formed at four corner portions of the electrolyte membrane 11. Communication ports 12d and 12g are formed at the upper left and lower right corner portions of the hydrogen-side current collector 12, respectively. Communication ports 13e and 13f are formed at the lower left and upper right corner portions of the oxygen-side current collector 13, respectively. Communication ports 14d to 14g are formed at four corner portions of the separator 14. Communication ports 15e and 15f are formed at the lower left and upper right corner portions of the flow path forming plate 15, respectively. Communication ports 14d to 14g are formed at four corner portions of the separator 16, respectively.

[0030] And the communication ports of the respective constituent members constituting the hydrogen production cell 10 described above are not connected to each other and are independent. Also, there is no interference in each constituent member. For example, a sealing material is provided around each communication port, or a sealing material is appropriately provided on the surface of each constituent member facing the electrode, that is, in the region corresponding to the electrolyte membrane 11, so that the reaction fluid is prevented from leaking from the end faces of the respective constituent members of the hydrogen production cell 10. The communication ports 11d and 11g of the electrolyte membrane 11 communicate with the communication ports 12d and 12g of the hydrogen-side current collector 12, the communication ports 14d and 14g of the separator 14, and the communication ports 16d and 16g of the separator 16, and lead to the hydrogen outlet ports P3 and P4 of the hydrogen production cell stack 4 described above. The communication ports 12d and 12g of the hydrogen-side current collector 12 constitute a recovery portion.

[0031] Similarly, the communication port 11e of the electrolyte membrane 11 communicates with the communication port 14e of the separator 14, the communication port 13e of the oxygen-side current collector 13, the communication port 15e of the flow path forming plate 15, and the communication port 16e of the separator 16, and leads to the pure water inlet port P1 of the hydrogen production cell stack 4. Also, the communication port 11f of the electrolyte membrane 11 communicates with the communication port 14f of the separator 14, the communication port 13f of the oxygen-side current collector 13, the communication port 15f of the flow path forming plate 15, and the communication port 16f of the separator 16, and leads to the pure water outlet port P2 of the hydrogen production cell stack 4.

[0032] The hydrogen production cell 10 according to the embodiment has the above configuration. Next, its operation and the like will be described. Pure water, which is the raw material water, is supplied from the pure water inlet port P1 of the hydrogen production cell stack 4 to each hydrogen production cell 10 in the hydrogen production cell stack 4. Then, when a voltage is applied to each hydrogen production cell 10 from the DC power supply 5, as shown in FIG. 4, the pure water is electrolyzed, and water and hydrogen gas containing moisture are generated on the hydrogen-side current collector 12. And on the outer surface of the hydrogen-side current collector 12, there is no specially dedicated flow path for the reaction fluid, and moreover, since the hydrogen-side current collector 12 has voids inside (in the embodiment, the porosity is 50% to 90%), this water and the hydrogen gas containing moisture pass through the inside of the hydrogen-side current collector 12 and go toward the communication ports 12d and 12g as shown in FIG. 5. Then, the water and the hydrogen gas containing moisture are discharged from the communication ports 12d and 12g to the hydrogen outlet ports P3 and P4 of the hydrogen production cell stack 4.

[0033] On the other hand, in the oxygen-side current collector 13 of the hydrogen production cell 10, the pure water that is supplied from the communication port 13e and has not been electrolyzed and the generated oxygen gas flow out of the oxygen-side current collector 13 and toward the flow path forming plate 15 side. And as shown in FIGS. 3 and 4, due to the presence of the flow path forming plate 15 having the unevenness 15a, a dedicated flow path 15b for the reaction fluid is formed between the oxygen-side current collector 13 and the flow path forming plate 15. Therefore, the pure water that has not been decomposed and the generated oxygen gas go toward the communication port 15f and are discharged to the pure water outlet port P2 of the hydrogen production cell stack 4 as shown in FIG. 6.

[0034] As described above, according to the hydrogen production cell 10 of this embodiment, it is not necessary to provide a separator of a conventional flow path forming plate or a separator having a flow path forming member on the outer surface of the hydrogen-side current collector 12. Therefore, the thickness per cell can be reduced compared to the conventional case. Along with this, the number of parts can be reduced and the structure can be simplified.

[0035] Furthermore, since the separator located on the outer surface of the hydrogen-side current collector 12 is flat without unevenness or the like on the surface, the hydrogen-side current collector 12 with extremely low rigidity can be brought into contact with the electrolyte membrane 11 over its entire surface. Therefore, the adhesion between the electrolyte membrane 11 serving as the electrode and the hydrogen-side current collector 12 is improved. In the case of a conventional separator having unevenness for forming a flow path plate or a flow path on the outer surface of the hydrogen-side current collector 12, it was a line contact or a point contact with the ridge or convex part of the groove. In comparison, the contact area increases and the contact resistance decreases. Therefore, the performance itself as a hydrogen production cell is improved.

[0036] Moreover, since the electrolyte membrane 11 and the hydrogen-side current collector 12 are pressed and contact over the entire surface, the reaction proceeds over the entire electrode surface. As a result, the deterioration itself also proceeds almost uniformly over the entire surface, and the substantial current density can also be kept low. Conventionally, on the other hand, as described above, the reaction proceeds only at the contact portions such as the ridges and convex portions. As a result, the contact portion deteriorates earlier than other portions and reaches the end of its life without effectively using the entire electrode surface. Also, the surface pressure is higher in the contact portion than in other regions, and acceleration of membrane thinning due to mechanical and chemical factors occurs, so there is also a risk of short circuit where the electrodes of both poles come into contact. In this regard, in the above-described embodiment, since the electrolyte membrane 11 and the hydrogen-side current collector 12 are pressed and contact over the entire surface, such a risk can be greatly suppressed.

[0037] Furthermore, in the hydrogen production cell 10 according to the above-described embodiment, the amount of hydrogen present in the cell during the reaction can be made extremely small. Therefore, even if hydrogen and oxygen are mixed due to a membrane breakage or the like, the possibility of combustion is extremely low because there is little hydrogen serving as fuel.

[0038] By the way, when the electrode size is large, it is necessary to provide a plurality of communication ports 12d and 12g that function as manifolds for draining and exhausting, that is, for collecting and discharging moisture and hydrogen gas. This is because these reaction fluids flow inside the hydrogen-side current collector 12, and the flow path resistance at that time is high. Also, if the distance from the location where water and hydrogen are generated to the communication port is too long, force may be locally applied to the membrane, and the membrane may be deformed or damaged.

[0039] To suppress this, for example, as in the hydrogen-side current collector 51 shown in FIG. 7, a plurality of communication ports 51d and 51g are provided on the opposing long side portions of the hydrogen-side current collector 51, and the overall shape is rectangular, so that the distance from the location where hydrogen is generated to the communication ports 51d and 51g can be shortened. That is, the shortest distance from the location where hydrogen is generated to the closest communication ports 51d and 51g can be shortened. Half of the distance L shown in FIG. 7 is the shortest distance. Incidentally, the length of the distance L suitable for the present invention is preferably, for example, 200 mm or less, although it also depends on the size of the entire electrode. In such a case, since the pressure loss is large on the oxygen-side raw water inlet side and the oxygen-side reaction fluid outlet side, as shown in FIG. 7, the oxygen-side communication ports 51h and 51i are set larger than the hydrogen-side communication ports 51d and 51g.

[0040] Of course, when the electrode area is small, for example, in the case of around 30 cm 2 Before and after, two communication ports 12d and 12g located on the diagonal of the hydrogen-side current collector 12, like the hydrogen-side current collector 12 used in the hydrogen production cell 10 according to the previous embodiment shown in FIG. 5, are sufficient.

[0041] Also, the hydrogen-side current collector used in the present invention is preferably made of a material that easily absorbs the generated water and hydrogen. This is because if the absorbability is poor, water and hydrogen will accumulate between the electrolyte membrane and the hydrogen-side current collector, causing membrane deformation. Therefore, examples of suitable materials for the hydrogen-side current collector used in the present invention include carbon paper and carbon non-woven fabric. In addition, as the electrolyte membrane used in the present invention, those in which the size of the membrane hardly changes between the dry state and the wet state are suitable. This is to suppress local application of force. Therefore, from this point of view, examples of materials suitable for the electrolyte membrane of the present invention include fluorine-based electrolyte membranes, alkali-based electrolyte membranes, hydrocarbon-based electrolyte membranes, and the like.

[0042] Furthermore, regarding the thickness of the hydrogen-side current collector, the greater the thickness, the lower the flow path resistance, and the easier it is to absorb the generated water and hydrogen. The suitable thickness for the present invention depends on the material constituting the hydrogen-side current collector and the porosity, but for example, a thickness of about 0.2 mm to 2.0 mm is preferable.

[0043] In addition, the following inventions can also be proposed. (1) An oxygen-side current collector and a hydrogen-side current collector are arranged on both sides of a solid polymer electrolyte having electrode catalyst layers formed on both sides, and a separator is arranged outside each of the oxygen-side current collector and the hydrogen-side current collector, and the oxygen-side current collector and the hydrogen-side current collector are sandwiched, and a hydrogen production cell for producing hydrogen by electrolyzing water, The hydrogen-side current collector has a large number of voids that are organically connected inside, and the surface of the separator arranged outside the hydrogen-side current collector on the hydrogen-side current collector side is flat, A hydrogen production cell, characterized in that no dedicated flow path for recovering the reaction fluid generated during electrolysis is formed between the separator arranged outside the hydrogen-side current collector and the hydrogen-side current collector. (2) The hydrogen production cell according to (1) above, characterized in that the porosity of the hydrogen-side current collector is 50% to 99%. (3) The hydrogen production cell according to any one of (1) or (2) above, characterized in that the hydrogen gas and water recovery parts generated from the hydrogen-side current collector are respectively formed at a set of opposing side parts of the hydrogen-side current collector. (4) The hydrogen production cell according to (3) above, characterized in that a plurality of the recovery parts are respectively formed at the opposing side parts. (5) The hydrogen-side current collector has a shape with a long side and a short side, and the recovery portions are respectively formed on the opposing long side portions. The hydrogen production cell according to any one of (3) or (4) above is characterized in this regard. (6) A hydrogen production method using the hydrogen production cell according to any one of (1) to (5) above, wherein a voltage is applied between the oxygen-side current collector and the hydrogen-side current collector to generate hydrogen gas from the hydrogen-side current collector.

Industrial Applicability

[0044] The present invention is useful for a hydrogen production cell that provides raw water and generates hydrogen by electrolyzing the raw water.

Explanation of Reference Numerals

[0045] 1 Hydrogen production apparatus 2, 3 End plates 4 Hydrogen production cell stack 5 DC power supply 10 Hydrogen production cell 11 Electrolyte membrane 11a Solid polymer membrane 11d to 11g Communication ports 12 Hydrogen-side current collector 12d, 12g Communication ports 13 Oxygen-side current collector 13e, 13f Communication ports 14 Separator 14d to 14g Communication ports 15 Flow path forming plate 15b Flow path 16 Separator 16d to 16g Communication ports P1 Pure water inlet port P2 Pure water outlet port P3, P4 Hydrogen outlet ports

Claims

1. A hydrogen generating cell for producing hydrogen by water electrolysis, comprising an oxygen-side current collector and a hydrogen-side current collector disposed on both sides of an electrolyte membrane, the oxygen-side current collector and the hydrogen-side current collector sandwiched between separators disposed on the outside of the oxygen-side current collector and the hydrogen-side current collector, the surface of the separator disposed outside the hydrogen-side current collector that comes into contact with the surface of the hydrogen-side current collector is flat; a dedicated flow path for recovering a reaction fluid generated during electrolysis is not formed between the separator and the hydrogen-side current collector; the surface of the separator and the surface of the hydrogen-side current collector are in direct contact with each other, a hydrogen generating cell, characterized in that a recovery section for the reaction fluid generated from the hydrogen-side current collector is formed at a position opposite to the recovery section, sandwiching a location on the hydrogen-side current collector where the reaction fluid is generated, so that the shortest distance from the location where the reaction fluid is generated to the recovery section is short.

2. A hydrogen generating cell for producing hydrogen by water electrolysis, comprising an oxygen-side current collector and a hydrogen-side current collector disposed on both sides of an electrolyte membrane, the oxygen-side current collector and the hydrogen-side current collector sandwiched between separators disposed on the outside of the oxygen-side current collector and the hydrogen-side current collector, the surface of the separator disposed outside the hydrogen-side current collector that comes into contact with the surface of the hydrogen-side current collector is flat; a dedicated flow path for recovering a reaction fluid generated during electrolysis is not formed between the separator and the hydrogen-side current collector; the surface of the separator and the surface of the hydrogen-side current collector are in direct contact with each other, a hydrogen generating cell, characterized in that a recovery section for a reaction fluid generated from the hydrogen-side current collector is formed by forming a plurality of recovery sections on a pair of opposing sides of the hydrogen-side current collector so as to shorten the shortest distance from the location where the reaction fluid is generated to the recovery section.

3. A hydrogen production cell described in either claim 1 or 2, characterized in that the hydrogen side collector is formed from carbon paper or carbon non-woven fabric, which is a material that easily absorbs hydrogen.

4. A hydrogen production cell described in any one of claims 1 or 2, characterized in that the material of the electrolyte membrane is either a fluorine-based electrolyte membrane, an alkaline electrolyte membrane or a hydrocarbon-based electrolyte membrane.

5. A hydrogen production cell described in any one of claims 1 to 4, characterized in that each of the recovery sections is formed in multiple sections.

6. A hydrogen production cell as described in Claim 5, characterized in that the multiple recovery sections formed on the opposing side portions are arranged at intervals.

7. In each of the opposing side portions, a plurality of oxygen-side communication ports and a plurality of hydrogen-side communication ports are arranged in a row along each side, 7. The hydrogen generating cell according to claim 6, wherein the hydrogen-side communication port is disposed between a plurality of oxygen-side communication ports.

8. The recovery section is a communication port, 8. The hydrogen generating cell according to claim 1, wherein the communication ports of the oxygen-side current collector, which serve as a raw water inlet and a reaction fluid outlet, are set larger than the communication ports of the hydrogen-side current collector.

9. A hydrogen production cell described in any one of claims 1 to 8, characterized in that a dedicated flow path through which a reaction fluid flows is formed between a separator arranged outside the oxygen side collector and the oxygen side collector.

10. A hydrogen generating cell as described in any one of claims 1 to 9, characterized in that the porosity of the hydrogen-side current collector is 50% to 99%.

11. A hydrogen production method using the hydrogen production cell according to any one of claims 1 to 10, A method for producing hydrogen, comprising applying a voltage between the oxygen-side current collector and the hydrogen-side current collector to generate hydrogen gas from the hydrogen-side current collector.

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