JP2014040636A - Differential pressure type water electrolysis apparatus - Google Patents

Abstract

An object of the present invention is to reduce damage to a solid polymer electrolyte membrane as much as possible with a simple and economical configuration and to improve power efficiency.
A unit cell 12 constituting a differential pressure water electrolysis apparatus 10 includes an electrolyte membrane / electrode structure 32, and the electrolyte membrane / electrode structure 32 is provided on both sides of a solid polymer electrolyte membrane 38 with anode feeders. 40 and cathode power supply 42 are provided. The solid polymer electrolyte membrane 38 includes a first electrolyte layer 38a disposed on the cathode power supply body 42 side and a second electrolyte layer 38b disposed on the anode power supply body 40 side, and the first electrolyte layer. While 38a is constituted by a hydrocarbon film, the second electrolyte layer 38b is constituted by a fluorine film.
[Selection] Figure 3

Description

  The present invention relates to a differential pressure type water electrolysis apparatus that electrolyzes water to generate oxygen on the anode side and generates hydrogen at a higher pressure than the oxygen on the cathode side.

  For example, hydrogen gas is used as a fuel gas for generating power from a fuel cell. Generally, when producing hydrogen gas, a water electrolysis apparatus is employed. This water electrolysis apparatus uses a solid polymer electrolyte membrane in order to electrolyze water and generate hydrogen (and oxygen). An electrode catalyst layer is provided on both sides of the solid polymer electrolyte membrane to constitute an electrolyte membrane / electrode structure, and a power feeder is provided on each side of the electrolyte membrane / electrode structure. Is configured.

  Therefore, in a state where a plurality of units are stacked, a voltage is applied to both ends in the stacking direction, and water is supplied to the anode power feeder. For this reason, water is decomposed and hydrogen ions (protons) are generated on the anode side of the electrolyte membrane / electrode structure, and the hydrogen ions permeate the solid polymer electrolyte membrane and move to the cathode side to bond with electrons. Thus, hydrogen is produced. On the other hand, on the anode side, oxygen produced together with hydrogen is discharged from the unit with excess water.

  As this type of solid polymer electrolyte membrane, for example, a cation exchange membrane (fluororesin sulfonic acid cation exchange membrane) is used (Patent Document 1). A solid polymer electrolyte membrane is constructed by chemically bonding a porous anode and cathode made of a noble metal, in particular, a platinum group metal, on both surfaces of the cation exchange membrane by chemical electroless plating.

JP-A-8-134679

  By the way, the above fluororesin-based solid polymer electrolyte membrane has good stretchability. For this reason, in particular, in a differential pressure type water electrolysis apparatus in which high-pressure hydrogen (hydrogen higher than generated oxygen) is generated on the cathode side, the solid polymer electrolyte membrane can be deformed along the opening shape of the anode feeder. is there. Therefore, there is an advantage that damage to the solid polymer electrolyte membrane is reduced.

  However, the fluororesin-based solid polymer electrolyte membrane has a problem that hydrogen gas permeability is high and current efficiency is lowered. At that time, if the film thickness is set large in order to improve the current efficiency, the voltage efficiency is lowered. As a result, there is a problem that the power efficiency cannot be easily improved.

  The present invention solves this type of problem, and with a simple and economical configuration, it is possible to suppress damage to the solid polymer electrolyte membrane as much as possible and to easily improve power efficiency. It aims at providing a differential pressure type water electrolysis device.

  The present invention provides a solid polymer electrolyte membrane, an anode power feeding body and a cathode power feeding body provided on both sides of the solid polymer electrolyte membrane, and opposed to the anode power feeding body, and is supplied with water. And an anode side separator that electrolyzes the water to generate oxygen and a cathode side that is disposed opposite to the cathode power supply and that electrolyzes the water to generate hydrogen at a pressure higher than that of the oxygen The present invention relates to a differential pressure type water electrolysis apparatus comprising a separator and a pressing member that presses the cathode power supply body toward the solid polymer electrolyte membrane.

  The solid polymer electrolyte membrane includes a first electrolyte layer disposed on the cathode power feeder side and a second electrolyte layer disposed on the anode power feeder side, and the first electrolyte layer includes the second electrolyte layer. While the current efficiency is higher than that of the electrolyte layer, the second electrolyte layer is set to have higher extensibility than the first electrolyte layer.

  Moreover, in this differential pressure type water electrolysis apparatus, it is preferable that the first electrolyte layer is constituted by a hydrocarbon film.

  Furthermore, in this differential pressure type water electrolysis apparatus, the second electrolyte layer is preferably composed of a fluorine-based film.

  Furthermore, in this differential pressure type water electrolysis apparatus, it is preferable that the second electrolyte layer has a thickness that is set based on the opening diameter of the contact member on the side opposite to the first electrolyte layer.

  Further, in this differential pressure type water electrolysis apparatus, a seal portion that surrounds the electrolysis region with a seal member is provided, and the seal portion sandwiches only a single layer of the solid polymer electrolyte membrane in the layer thickness direction. Is preferred.

  Furthermore, in this differential pressure type water electrolysis apparatus, it is preferable that the seal portion sandwiches only the second electrolyte layer of the solid polymer electrolyte membrane in the layer thickness direction.

  According to the present invention, the solid polymer electrolyte membrane employs a multilayer structure having at least a first electrolyte layer and a second electrolyte layer. Here, the 2nd electrolyte layer arrange | positioned at the anode electric power feeding body side is set more highly than the 1st electrolyte layer. For this reason, when the solid polymer electrolyte membrane is pressed from the high-pressure cathode power supply side to the low-pressure anode power supply side, the second electrolyte layer on the anode power supply side expands and contracts well. Therefore, even when pressed at a high pressure, damage to the solid polymer electrolyte membrane constituting the first electrolyte layer having low extensibility is made possible by the solid polymer electrolyte membrane constituting the second electrolyte layer as much as possible. Can be suppressed.

  On the other hand, the first electrolyte layer disposed on the cathode power supply side is set to have higher current efficiency than the second electrolyte layer. As a result, the power efficiency can be improved more easily than when the second electrolyte layer is used alone.

It is a perspective explanatory view of a differential pressure type water electrolysis device concerning a 1st embodiment of the present invention. It is a disassembled perspective explanatory drawing of the unit cell which comprises the said differential pressure type water electrolysis apparatus. FIG. 3 is a cross-sectional view of the unit cell taken along line III-III in FIG. 2. It is a principal part expansion explanatory drawing of the solid polymer electrolyte membrane which comprises the said unit cell. It is explanatory drawing of a film thickness and efficiency in a fluorine-type film | membrane. It is explanatory drawing of a film thickness and efficiency in a hydrocarbon-type film | membrane. It is sectional drawing of the unit cell which comprises the differential pressure type water electrolysis apparatus which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the unit cell which comprises the differential pressure type water electrolysis apparatus which concerns on the 3rd Embodiment of this invention. It is sectional drawing of the unit cell which comprises the differential pressure type water electrolysis apparatus which concerns on the 4th Embodiment of this invention.

  As shown in FIG. 1, the differential pressure type water electrolysis apparatus (high pressure water electrolysis apparatus) 10 according to the first embodiment of the present invention has a plurality of unit cells 12 in a vertical direction (arrow A direction) or a horizontal direction (arrow B). The laminate 14 is laminated in the direction).

  At one end (upper end) in the stacking direction of the stacked body 14, a terminal plate 16a, an insulating plate 18a, and an end plate 20a are sequentially disposed upward. Similarly, a terminal plate 16b, an insulating plate 18b, and an end plate 20b are sequentially disposed on the other end (lower end) in the stacking direction of the stacked body 14 in a downward direction.

  The differential pressure type water electrolysis apparatus 10 integrally holds and holds the disc-shaped end plates 20a and 20b via four tie rods 22 extending in the direction of arrow A, for example. In addition, the differential pressure type water electrolysis apparatus 10 may adopt a configuration in which it is integrally held by a box-like casing (not shown) including end plates 20a and 20b as end plates. Moreover, although the differential pressure type water electrolysis apparatus 10 has a substantially cylindrical shape as a whole, it can be set in various shapes such as a cubic shape.

  Terminal portions 24a and 24b are provided on the side portions of the terminal plates 16a and 16b so as to protrude outward. The terminal portions 24a and 24b are electrically connected to the electrolytic power source 28 via the wirings 26a and 26b.

  As shown in FIGS. 2 and 3, the unit cell 12 includes a substantially disc-shaped electrolyte membrane / electrode structure 32, and an anode separator 34 and a cathode separator 36 that sandwich the electrolyte membrane / electrode structure 32. Prepare. The anode-side separator 34 and the cathode-side separator 36 have a substantially disk shape and are made of, for example, a carbon member or the like, or a steel plate, a stainless steel plate, a titanium plate, an aluminum plate, a plated steel plate, or a metal surface thereof. A metal plate subjected to an edible surface treatment is press-molded or cut and subjected to an anticorrosive surface treatment.

  The electrolyte membrane / electrode structure 32 includes a solid polymer electrolyte membrane 38, and an anode anode feeder 40 and a cathode feeder 42 having a circular shape provided on both surfaces of the solid polymer electrolyte membrane 38.

  The solid polymer electrolyte membrane 38 has two or more layers, for example, two layers of a first electrolyte layer 38a disposed on the cathode power supply 42 side and a second electrolyte layer 38b disposed on the anode power supply 40 side. Have The first electrolyte layer 38a has higher current efficiency than the second electrolyte layer 38b, while the second electrolyte layer 38b is set to have higher extensibility than the first electrolyte layer 38a.

  Specifically, the first electrolyte layer 38a is configured by, for example, a hydrocarbon (HC) -based film, while the second electrolyte layer 38b is configured by, for example, a fluorine-based film. Note that the first electrolyte layer 38a may not be a hydrocarbon-based film, and the second electrolyte layer 38b may not be a fluorine-based film. Even when other film types are used, a film that is more extensible than the first electrolyte layer 38a may be used as the film used for the second electrolyte layer 38b.

  The external dimensions of the first electrolyte layer 38a are set to be the same as the outer diameter dimensions of the anode power supply body 40 and the cathode power supply body 42, that is, the dimensions corresponding to the electrolysis region, and the external dimensions of the second electrolyte layer 38b are The outer diameter of the anode power supply body 40 and the cathode power supply body 42 is set larger than the outer diameter (see FIG. 3). The second electrolyte layer 38b has a thickness that is set based on the opening diameter of the anode power supply body 40 that is a contact member on the side opposite to the first electrolyte layer 38a. That is, the thickness of the second electrolyte layer 38b is set to a dimension that can be easily deformed following the opening shape of the anode power supply body 40.

  An anode electrode catalyst layer 40a and a cathode electrode catalyst layer 42a are formed on both surfaces of the solid polymer electrolyte membrane 38. The anode electrode catalyst layer 40a uses, for example, a Ru (ruthenium) -based catalyst, and is provided on the second electrolyte layer 38b. On the other hand, the cathode electrode catalyst layer 42a uses, for example, a platinum catalyst, and forms the first electrolyte layer 38a on the first electrolyte layer 38a. Provided.

  The anode power supply body 40 is constituted by, for example, a sintered body (porous conductor) of spherical atomized titanium powder. The anode power supply body 40 is provided with a smooth surface portion to be etched after the grinding process, and the porosity is set within a range of 10% to 50%, more preferably 20% to 40%.

  The cathode power supply 42 is a porous conductor formed integrally with the plate member 44 by, for example, low-pressure plasma spraying using pure titanium particles as a spraying material. The porosity of the porous conductor is set within a range of 10% to 50%.

  The plate member 44 has a disk shape, and a pressing member, for example, a plurality of disc springs 46, is disposed on the load applying surface 44b opposite to the sprayed surface 44a on which the cathode power supply 42 is sprayed. . The disc spring 46 applies a load to the cathode power supply body 42 via a plate member 44 that is a disc spring holder.

  As shown in FIG. 2, a first protrusion 48 a, a second protrusion 48 b, and a third protrusion 48 c that protrude outward in the separator surface direction are formed on the outer periphery of the unit cell 12. The first protrusion 48a is provided with a water supply communication hole 50a that communicates with each other in the direction of arrow A that is the stacking direction and supplies water (pure water) that is the first fluid.

  The second projecting portion 48b is provided with a discharge communication hole 50b that communicates with each other in the direction of the arrow A and discharges oxygen generated by the reaction and used water. The third protrusion 48c is provided with a hydrogen communication hole 50c that is in communication with each other in the direction of arrow A, which is the stacking direction, for flowing high-pressure hydrogen generated by the reaction.

  As shown in FIGS. 2 and 3, the anode-side separator 34 is provided with a supply passage 52a that communicates with the water supply communication hole 50a and a discharge passage 52b that communicates with the discharge communication hole 50b. A first flow path 54 communicating with the supply passage 52a and the discharge passage 52b is provided on the surface 34a of the anode separator 34 facing the electrolyte membrane / electrode structure 32. The first flow path 54 is provided in a range corresponding to the contact area range of the anode power supply body 40.

  The cathode separator 36 is provided with a discharge passage 56 that communicates with the hydrogen communication hole 50c. A second flow path 58 communicating with the discharge passage 56 is formed on the sprayed surface 44 a of the plate member 44. The second flow path 58 is provided in a range corresponding to the contact area range of the cathode power supply body 42. Note that the second flow path 58 may be formed in the porous space inside the cathode power supply 42 without providing the second flow path 58 on the sprayed surface 44a.

  The seal members 60a and 60b are integrated with each other around the outer peripheral ends (electrolytic regions) of the anode side separator 34 and the cathode side separator 36. The seal members 60a and 60b include, for example, EPDM, NBR, fluorine rubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene or acrylic rubber, seal materials, cushion materials, packing materials, etc. A sealing member having the elasticity is used.

  As shown in FIGS. 2 and 3, a second seal member is formed on the surface 34 a of the anode separator 34 facing the electrolyte membrane / electrode structure 32 so as to circulate outward from the first flow path 54 and the anode power feeder 40. A second seal groove 64a for disposing 62a is formed.

  On the surface 34a, a third seal member 62b, a fourth seal member 62c, and a fifth seal member 62d are arranged around the outside of the water supply communication hole 50a, the discharge communication hole 50b, and the hydrogen communication hole 50c. A third seal groove 64b, a fourth seal groove 64c, and a fifth seal groove 64d are formed. The second seal member 62a to the fifth seal member 62d are, for example, O-rings.

  The first seal member 66a is disposed on the surface 36a of the cathode separator 36 facing the electrolyte membrane / electrode structure 32 so as to circulate outwardly from the second flow path 58 and the cathode power feeder 42. A seal groove 68a is formed.

  At least the first seal member 66a and the first seal groove 68a constitute a seal portion 69 that surrounds the electrolysis region, and the seal portion 69 includes only a single layer of the solid polymer electrolyte membrane 38. In the embodiment, only the second electrolyte layer 38b is sandwiched in the layer thickness direction (arrow A direction). Specifically, the second electrolyte layer 38b is sandwiched between the first seal member 66a and the anode-side separator 34.

  On the surface 36a, the third seal member 66b, the fourth seal member 66c, and the fifth seal member 66d are disposed around the outside of the water supply communication hole 50a, the discharge communication hole 50b, and the hydrogen communication hole 50c. A third seal groove 68b, a fourth seal groove 68c, and a fifth seal groove 68d are formed. The first seal member 66a, the third seal member 66b to the fifth seal member 66d are, for example, O-rings.

  The second seal groove 64a that goes around the outside of the anode power supply body 40 and the first seal groove 68a that goes around the outside of the cathode power supply body 42 are solid polymer electrolyte membranes with respect to the separator stacking direction (arrow A direction). 38 are set at different positions.

  The fifth seal groove 64d that circulates outward from the hydrogen communication hole 50c and the fifth seal groove 68d that circulates outward from the hydrogen communication hole 50c sandwich each other across the solid polymer electrolyte membrane 38 in the direction of arrow A. Set to a different position.

  As shown in FIG. 1, pipes 76a, 76b and 76c communicating with the water supply communication hole 50a, the discharge communication hole 50b and the hydrogen communication hole 50c are connected to the end plate 20a. Although not shown, the pipe 76c is provided with a back pressure valve (or electromagnetic valve), and the pressure of hydrogen generated in the hydrogen communication hole 50c can be maintained at a high pressure. A pressing force is applied between the end plates 20 a and 20 b by a pressing force applying device (not shown), and the end plates 20 a and 20 b are tightened via the tie rods 22 in this state.

  The operation of the differential pressure type water electrolysis apparatus 10 configured as described above will be described below.

  As shown in FIG. 1, water is supplied from a pipe 76a to the water supply communication hole 50a of the differential pressure water electrolysis apparatus 10, and is electrically connected to the terminal portions 24a and 24b of the terminal plates 16a and 16b. A voltage is applied via the power supply 28. Therefore, as shown in FIGS. 2 and 3, in each unit cell 12, water is supplied from the water supply communication hole 50 a to the first flow path 54 of the anode-side separator 34, and this water enters the anode power supply body 40. Move along.

  Accordingly, water is decomposed by electricity in the anode electrode catalyst layer 40a, and hydrogen ions, electrons, and oxygen are generated. Hydrogen ions generated by this anodic reaction permeate the solid polymer electrolyte membrane 38 and move to the cathode electrode catalyst layer 42a side, and combine with electrons to obtain hydrogen.

  For this reason, hydrogen flows along the inside of the cathode power supply 42 and the second flow path 58 formed in the plate member 44. This hydrogen is maintained at a pressure higher than that of the water supply communication hole 50a, and can flow out of the differential pressure water electrolysis apparatus 10 through the hydrogen communication hole 50c. On the other hand, oxygen generated by the reaction and used water flow in the first flow path 54, and these are discharged to the outside of the differential pressure water electrolysis apparatus 10 along the discharge communication hole 50b.

  In this case, in the first embodiment, as shown in FIG. 3, the solid polymer electrolyte membrane 38 employs a multilayer structure having at least a first electrolyte layer 38a and a second electrolyte layer 38b. Here, the second electrolyte layer 38b disposed on the anode power supply body 40 side is formed of, for example, a fluorine-based film. The fluorine-based film has good stretchability. As shown in FIG. 4, when a differential pressure is applied to the solid polymer electrolyte film 38, the second electrolyte layer 38 b Deforms following the shape of the porous surface. Accordingly, the solid polymer electrolyte membrane 38 can suppress damage as much as possible even when a considerably large differential pressure is applied.

  However, the fluorine-based film has properties of high gas permeability and low current efficiency. The film thickness and efficiency of this fluorine-based film have the relationship shown in FIG. For this reason, when the film thickness is set thick in order to increase the current efficiency, the voltage efficiency is lowered and the power efficiency is lowered.

  On the other hand, the first electrolyte layer 38a disposed on the cathode power supply 42 side is made of, for example, a hydrocarbon film. The hydrocarbon film is inferior in stretchability to the fluorine film, but has low gas permeability and high current efficiency. As shown in FIG. 6, the hydrocarbon-based film maintains a relatively high current efficiency, and the maximum power efficiency can be obtained by selecting the film thickness.

  Thereby, in the first embodiment, it is possible to suppress damage to the solid polymer electrolyte membrane 38 as much as possible with a simple and economical configuration, and to easily improve power efficiency. Is obtained.

  Furthermore, in the first embodiment, the second electrolyte layer 38 b has a thickness that is set based on the opening diameter of the anode power supply body 40. For this reason, as shown in FIG. 4, even when the solid polymer electrolyte membrane 38 is pushed into the opening of the anode power feeder 40, the second electrolyte layer 38 b is surely attached to the porous surface of the anode power feeder 40. It becomes possible to touch.

  Furthermore, as shown in FIG. 3, the seal portion 69 includes only a single layer of the solid polymer electrolyte membrane 38, and in the first embodiment, only the second electrolyte layer 38b in the layer thickness direction (direction of arrow A). ). Specifically, the second electrolyte layer 38 b is sandwiched between the first seal member 66 a and the anode separator 34.

  Here, the 2nd electrolyte layer 38b is comprised by the fluorine-type film | membrane excellent in the extensibility, and the favorable followable | trackability at the time of load fluctuation | variation is obtained. Moreover, even when the flatness of the separator surface is rough, the solid polymer electrolyte membrane 38 can be prevented from being damaged.

  FIG. 7 is a cross-sectional view of a unit cell 82 constituting a differential pressure water electrolysis apparatus 80 according to the second embodiment of the present invention. The same constituent elements as those of the differential pressure type water electrolysis apparatus 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Similarly, in the third and subsequent embodiments described below, detailed description thereof is omitted.

  In the unit cell 82, a protective sheet member 84 in which a large number of through holes 84 a are formed is interposed between the solid polymer electrolyte membrane 38 and the anode power supply body 40. The protective sheet member 84 is made of, for example, a titanium sheet, and the thickness is set within a range of 20 μm to 500 μm, for example. The surface roughness of the titanium sheet is set to 6.3 μm or less, preferably 3.2 μm or less. This titanium sheet is preferably formed by cold rolling.

  The through hole 84 a is set such that the distribution width of the hole diameter of the through hole 84 a is smaller than the distribution width of the hole diameter of the hole portion of the anode power supply body 40.

  In the second embodiment configured as described above, when the solid polymer electrolyte membrane 38 is pressed against the protective sheet member 84, the second electrolyte layer 38 b of the solid polymer electrolyte membrane 38 is applied to the protective sheet member 84. Pressed. At this time, the second electrolyte layer 38 b is configured by a fluorine-based film, and the second electrolyte layer 38 b can be deformed along the surface shape of the protective sheet member 84. As a result, the same effects as those of the first embodiment can be obtained, for example, it is possible to suppress damage to the solid polymer electrolyte membrane 38 as much as possible.

  FIG. 8 is a cross-sectional view of a unit cell 92 constituting a differential pressure water electrolysis apparatus 90 according to the third embodiment of the present invention.

  The unit cell 92 includes an electrolyte membrane / electrode structure 94, and the electrolyte membrane / electrode structure 94 includes a solid polymer electrolyte membrane 96. The solid polymer electrolyte membrane 96 has two or more layers, for example, two layers of a first electrolyte layer 96a disposed on the cathode power supply 42 side and a second electrolyte layer 96b disposed on the anode power supply 40 side. Have

  The first electrolyte layer 96a is composed of, for example, a hydrocarbon (HC) film, while the second electrolyte layer 96b is composed of, for example, a fluorine film. The external dimensions of the second electrolyte layer 96b are set to be the same as the outer diameter dimensions of the anode power supply body 40 and the cathode power supply body 42, that is, the dimensions corresponding to the electrolysis region, and the external dimensions of the first electrolyte layer 96a are The anode power supply body 40 and the cathode power supply body 42 are set to have larger diameters than the outer diameter dimensions thereof.

  The seal portion 69 sandwiches only a single layer of the solid polymer electrolyte membrane 96, in the third embodiment, only the first electrolyte layer 96a in the layer thickness direction (arrow A direction). Specifically, the first electrolyte layer 96a is sandwiched between the first seal member 66a and the anode-side separator 34.

  In the third embodiment configured as described above, only the first electrolyte layer 96a constituting the solid polymer electrolyte membrane 96 is interposed between the first seal member 66a constituting the seal portion 69 and the anode-side separator 34. It is pinched. For this reason, the sag of the solid polymer electrolyte membrane 96 is one layer. Therefore, even when a sag occurs in the solid polymer electrolyte membrane 96 due to a long-term operation, it is possible to suppress the fluctuation of the load and to obtain an effect that it is possible to maintain a good pressing action.

  FIG. 9 is a cross-sectional view of the unit cell 102 constituting the differential pressure water electrolysis apparatus 100 according to the fourth embodiment of the present invention.

  The unit cell 102 includes an electrolyte membrane / electrode structure 104, and the electrolyte membrane / electrode structure 104 includes a solid polymer electrolyte membrane 106. The solid polymer electrolyte membrane 106 has two or more layers, for example, two layers of a first electrolyte layer 106a disposed on the cathode power supply 42 side and a second electrolyte layer 106b disposed on the anode power supply 40 side. Have

  The first electrolyte layer 106a is formed of, for example, a hydrocarbon (HC) film, while the second electrolyte layer 106b is formed of, for example, a fluorine film. The outer dimensions of the first electrolyte layer 106 a and the second electrolyte layer 106 b are set to be larger than the outer diameter dimensions of the anode power supply body 40 and the cathode power supply body 42.

  The seal portion 69 sandwiches the first electrolyte layer 106a and the second electrolyte layer 106b, which are two layers of the solid polymer electrolyte membrane 106, in the layer thickness direction (arrow A direction). Specifically, the first electrolyte layer 106a and the second electrolyte layer 106b are sandwiched between the first seal member 66a and the anode-side separator 34.

  In the fourth embodiment configured as described above, the same effect as in the first embodiment can be obtained.

DESCRIPTION OF SYMBOLS 10, 80, 90, 100 ... Differential pressure type water electrolysis apparatus 12, 82, 92, 102 ... Unit cell 14 ... Laminated body 16a, 16b ... Terminal plate 18a, 18a ... Insulating plate 20a, 20b ... End plate 24a, 24b ... Terminal Section 28 ... Electrolytic power source 32, 94, 104 ... Electrolyte membrane / electrode structure 34 ... Anode side separator 36 ... Cathode side separator 38, 96, 106 ... Solid polymer electrolyte membrane 38a, 38b, 96a, 96b, 106a, 106b ... Electrolyte layer 40 ... anode power supply 42 ... cathode power supply 46 ... disc spring 50a ... water supply communication hole 50b ... discharge communication hole 50c ... hydrogen communication hole 54, 58 ... flow paths 62a-62d, 66a-66d ... seal members 64a- 64d, 68a to 68d ... seal groove 69 ... seal portion 84 ... protective sheet member

Claims (6)

A solid polymer electrolyte membrane;
An anode feeder and a cathode feeder for electrolysis provided on both sides of the solid polymer electrolyte membrane;
An anode-side separator that is disposed opposite to the anode power feeding body, is supplied with water, and electrolyzes the water to generate oxygen;
A cathode-side separator that is disposed opposite to the cathode power supply and generates hydrogen having a pressure higher than that of oxygen by electrolyzing the water;
A pressing member that presses the cathode feeder toward the solid polymer electrolyte membrane;
A differential pressure type water electrolysis apparatus comprising:
The solid polymer electrolyte membrane includes a first electrolyte layer disposed on the cathode power supply side,
A second electrolyte layer disposed on the anode feeder side;
Have
The first electrolyte layer has a higher current efficiency than the second electrolyte layer, while the second electrolyte layer is set to have a higher extensibility than the first electrolyte layer. apparatus.   2. The differential pressure water electrolysis apparatus according to claim 1, wherein the first electrolyte layer is composed of a hydrocarbon film.   3. The differential pressure type water electrolysis apparatus according to claim 1, wherein the second electrolyte layer is composed of a fluorine-based film.   4. The differential pressure water electrolysis apparatus according to claim 1, wherein the second electrolyte layer is set based on an opening diameter of a contact member on a side opposite to the first electrolyte layer. 5. A differential pressure type water electrolysis apparatus comprising: In the differential pressure type water electrolysis device according to any one of claims 1 to 4, a seal portion that surrounds the electrolysis region with a seal member is provided,
The differential pressure type water electrolysis apparatus, wherein the seal portion sandwiches only a single layer of the solid polymer electrolyte membrane in a layer thickness direction.   6. The differential pressure type water electrolysis apparatus according to claim 5, wherein the seal portion sandwiches only the second electrolyte layer of the solid polymer electrolyte membrane in the layer thickness direction.

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