EP4166691A1 - Frame for pem electrolytic cells and pem electrolytic cell stack for producing high pressure hydrogen by means of differential pressure electrolysis - Google Patents

Abstract

The invention relates to a new frame for a PEM electrolytic cell and for a PEM electrolytic cell stack. The subject matter of the invention is the frame, a PEM electrolysis cell and a PEM electrolysis cell stack, which comprise the frame according to the invention, preassembled components and methods for producing the preassembled components and PEM electrolysis cell stack. The frame, PEM electrolysis cell and PEM electrolysis cell stack according to the invention are suitable for the production of high-pressure hydrogen in combination with the use of thin proton exchange membranes. The invention is based on a new frame and sealing concept.

Description

The invention relates to a new frame for a PEM electrolytic cell and for a PEM electrolytic cell stack. The subject matter of the invention is the frame, a PEM electrolytic cell and a PEM electrolytic cell stack, which comprise the frame according to the invention, preassembled assemblies, methods for producing the preassembled assemblies and methods for producing the PEM electrolytic cell stack. The frame according to the invention, the PEM electrolytic cell according to the invention and the PEM electrolytic cell stack according to the invention are suitable for generating high-pressure hydrogen by means of differential pressure electrolysis in combination with the use of thin proton exchange membranes. The invention is based on a new frame and sealing concept.

Proton exchange membrane (PEM) water electrolysis is an attractive technology for producing hydrogen using electricity derived from renewable energy sources. As a result, the energy can be stored in the energy carrier hydrogen for times when there is not enough electricity from renewable sources available, thereby contributing to decarbonization. An important advantage of PEM electrolysis is the possibility of generating hydrogen under pressure. Hydrogen must be available in compressed form for all potential areas of application, which means that PEM systems (e.g. PEM electrolysis cells and PEM electrolysis cell stacks) serve the needs of industry to a particular extent. For reasons of energy saving, it is advantageous to operate the PEM electrolysis directly under pressure, since less additional energy is required than with subsequent mechanical compression. Since usually only the hydrogen is used, the oxygen can be generated more cheaply without pressure, which is referred to as differential pressure electrolysis. A differential pressure of at least 30 bar is state of the art today, although this is currently only possible using PEM membranes with a thickness of at least approx. 120 µm.

In order to be able to generate as much hydrogen as possible with the available electricity, the efficiency in the PEM electrolysis cell is of outstanding importance. A significant proportion of the energy losses are caused by the ohmic resistances, especially at the PEM membrane. A PEM membrane is used catalyst coated membrane (CCM) used. The membrane resistance can be significantly reduced by using a thin PEM membrane.

The classic structure of a PEM electrolysis cell is in figure 1 shown.

A classic PEM electrolytic cell consists of a catalyst-coated membrane (CCM) on which the reaction takes place. On the anode and cathode sides, porous transport layers (PTL) transport the water towards the CCM and porous transport layers (PTL) transport the generated gas away from the CCM. The bipolar plate (BPP) spatially separates the anode and cathode sides. The inflow and outflow of gas and water is ensured by a frame made of classic metal or high-strength plastic (PEEK). The CCM and PTL components are inserted into this frame. The frame is laterally sealed by O-rings or other seals such as flat gaskets or injected inserted gaskets to prevent the gas from escaping the PEM electrolytic cell.

PEM electrolytic cells and PEM electrolytic cell stacks comprising frames are known in the prior art.

US 6,669,826 B1 discloses achieving sealing in a PEM electrolytic cell stack by uniform contact pressure on the electrolytic cells by compressing sub-stacks, each comprising a plurality of PEM electrolytic cells arranged in series in a bipolar array, by means of end plates, intermediate supports, tie rods and biasing means become.

US 6,852,441 B1 discloses stabilizing the frames of the PEM electrolytic cells in an electrolytic cell stack by a reinforcing element that surrounds the electrolytic cell stack peripherally.

EP 1 356 134 B1 discloses frames for PEM electrolytic cells in which the electrolytic cells are compactly stacked in a bipolar arrangement and the stacked frames are separated by partitions. The frames have two opposed planar surfaces and an opening in which the membrane is held in the frame by thermal compression bonding to polyphenylene oxide strips, holes for inlet of electrolyte and outlet for the generated gas. Gas and gas sealing is provided by O-rings and sealing of the stack by an array of O-rings in grooves in each frame. To the integrity of To maintain sealing rings between adjacent frames in a stack against internal pressure, the PEM electrolytic cell stack is sandwiched between two stainless steel plates held together by threaded tie rods and pressed together.

U.S. 8,282,811 B2 discloses electrolytic cells for generating hydrogen at high pressures, with frames which are arranged between membrane electrode assembly and separators which serve as hydrogen separators and oxygen separators, respectively, and which have openings for the passage of water, oxygen and hydrogen. Gaskets seal the frame on the separators while the membrane seals the frame on the opposite side. Pressure pads between adjacent separators and plastic manifold gaskets surrounding the pressure pads seal the openings between individual electrolytic cells in a stack.

U.S. 7,507,493 B2 discloses PEM electrolytic cells containing sealed bipolar plates. The gasket is positioned between the frame and an edge of the porous gas diffusion layer. In addition, the electrolytic cells have a protective element between the seal and the membrane electrode arrangement to protect the proton exchange membrane. This should allow the cell to work at sustained high pressures, low specific resistances and improved creep protection.

US 8,349,151 B2 discloses a frame for use as an anode frame and as a cathode frame in a water electrolyzer, the anode frame and cathode frame being of identical construction and comprising a universal cell frame having a central opening and a plurality of transverse openings, with mating sets of transverse openings being spaced about 90 or 180 degrees apart and each being fluidly connected or not connected to the central opening by at least one inner radial passage, and wherein the anode frame and cathode frame are rotated 90 degrees relative to one another such that a row of electrolysers are fluidly connected through the openings.

EP 3 462 528 A1 discloses an electrochemical cell for generating high pressure hydrogen with a membrane electrode assembly and flow structures having planar surfaces on both sides of the membrane electrode assembly, wherein the one planar Surface is larger than the other surface, in addition to the flow structure with the smaller surface, a bipolar plate, a reinforcing layer and a seal with a sealing ring between the bipolar plate and the electrolyte membrane are arranged.

DE 10 2014 010 813 A1 discloses a frame for a stack-type electrolyzer for high-pressure hydrogen production, the frame comprising an integral reinforcement disposed between the fluid guide and the outer periphery and embedded in the frame structure, and a receiving recess disposed radially between the reinforcement and the fluid guide a seal.

1. 1. Probleme bei der Dichtigkeit, da in einem PEM Elektrolysezellen Stapel Rahmen vieler PEM Elektrolysezellen aufeinandergestapelt werden und jedes in den Rahmen und den anderen Komponenten verwendete Material Fertigungstoleranzen aufweist. Dies kann dazu führen, dass für die O-Ringe oder andere verwendete Dichtungen an einigen Stellen nicht genug Anpresskraft herrscht. Vor allem wenn der Wasserstoff unter Druck bzw. Differenzdruck erzeugt wird, ist die Dichtigkeit mit den bekannten Dichtungen schwer oder gar schwer zu realisieren.
2. 2. Die mechanische Stabilität des Rahmens: Bei der Erzeugung von Hochdruck-Wasserstoff werden die Kunststoffrahmen verformt (Figur 2).
3. 3. Zwischen PTL und Rahmen 1 verbleibt ein kleiner Spalt 17. In diesen Spalt 17 wird die CCM 13 im Druckbetrieb eingedrückt. Es kommt zu Kriechen 24 (sog. viskoelastisches Verhalten)) der CCM 13 in den Spalt 17. Dieser Effekt wird verstärkt, wenn der Rahmen 1 aufgrund von geringer mechanischer Stabilität verformt wird (vergl. Pkt. 2), so dass der Spalt 17 größer wird (Figur 2).
4. 4. Der Rahmen umfasst Kanäle zum An- und Abtransport von Wasser und Gas. Die Kanäle werden aus dem Rahmen, d.h. aus dem Metall- oder Kunststoffteil ausgefräst, was hohe Kosten verursacht.

Difficulties that typically occur with classic PEM electrolysis cells:

1. 1. Problems with tightness, since frames of many PEM electrolytic cells are stacked on top of each other in a PEM electrolytic cell stack and each material used in the frame and the other components has manufacturing tolerances. This can mean that there is not enough contact pressure in some places for the O-rings or other seals used. Especially when the hydrogen is generated under pressure or differential pressure, it is difficult or even difficult to achieve tightness with the known seals.
2. 2. The mechanical stability of the frame: When generating high-pressure hydrogen, the plastic frames are deformed ( figure 2 ).
3. 3. A small gap 17 remains between the PTL and frame 1. The CCM 13 is pressed into this gap 17 during printing operation. The CCM 13 creeps 24 (so-called viscoelastic behavior) into the gap 17. This effect is intensified when the frame 1 is deformed due to low mechanical stability (see point 2), so that the gap 17 becomes larger becomes ( figure 2 ).
4. 4. The frame includes ducts for supplying and removing water and gas. The channels are milled out of the frame, ie out of the metal or plastic part, which causes high costs.

In order to be able to produce hydrogen under high pressure for industrial purposes by means of PEM electrolysis, an improved PEM electrolysis cell is required which can be operated under high pressure and differential pressure and which does not have the disadvantages mentioned above.

The object is solved by the invention according to claims 1 to 10.

• wobei der Anodenrahmen die erste Seite 4, eine der ersten Seite 4 gegenüberliegende Seite des Anodenrahmens 4" und eine erste Öffnung 6 zur Aufnahme der porösen Transportschicht (PTL) Anode 7 umfasst, wobei die erste Öffnung 6 sich von der ersten Seite 4 bis zur gegenüberliegenden Seite des Anodenrahmens 4" erstreckt,
• wobei der Kathodenrahmen 11 die zweite Seite 5, eine der zweiten Seite 5 gegenüberliegende Seite des Kathodenrahmens 5" und eine zweite Öffnung 9 zur Aufnahme der PTL Kathode 10 umfasst, wobei die zweite Öffnung 9 sich von der zweiten Seite 5 bis zur gegenüberliegenden Seite des Kathodenrahmens 5" erstreckt,
• wobei die der ersten Seite 4 gegenüberliegende Seite des Anodenrahmens 4" und die der zweiten Seite 5 gegenüberliegende Seite des Kathodenrahmens 5" nebeneinander angeordnet sind,
• wobei Anodenrahmen 8 und Kathodenrahmen 11 miteinander verbunden sind,
• wobei die erste Öffnung 6 und die zweite Öffnung 9 miteinander verbunden sind,
• wobei die erste Öffnung 6 größer ist als die zweite Öffnung 9 und wobei der Anodenrahmen 8 und der Kathodenrahmen 11 so angeordnet sind, dass die der ersten Seite 4 gegenüberliegende Seite des Anodenrahmens 4" und die der zweiten Seite 5 gegenüberliegende Seite des Kathodenrahmens 5", beim Übergang vom Anodenrahmen 8 zum Kathodenrahmen 11 einen Absatz 12 bilden, wobei der Absatz 12 der Teil des Kathodenrahmens 11 ist, der an die zweite Öffnung 9 angrenzt und die zweite Öffnung 9 umrahmt und wobei der Absatz 12 eine planare dritte Oberfläche als Auflagefläche für die Katalysator-beschichtete Membran (CCM) 13 bildet, und wobei der Anodenrahmen 8 einen Kern aus Metall 21 und eine Beschichtung aus einem Dichtwerkstoff, beispielsweise eine Beschichtung aus Gummi 22 umfasst und wobei der Kathodenrahmen 11 einen Kern aus Metall 21 und eine Beschichtung aus einem Dichtwerkstoff, beispielsweise eine Beschichtung aus Gummi 22 umfasst. Als Beschichtung für den Kern aus Metall 21 ist jeder Dichtwerkstoff geeignet, beispielsweise Gummi, insbesondere Ethylen-Propylen-Dien-Kautschuk (EPDM).

The invention relates to a frame 1 for a PEM electrolysis cell 2 for a PEM electrolysis device of the stack type 23, the frame 1 having a first side 4 with a planar first surface and a second side 5 opposite the first side 4 with a planar second surface and an anode frame 8 and a cathode frame 11 , and

• the anode frame comprising the first side 4, a side of the anode frame 4" opposite the first side 4 " and a first opening 6 for receiving the porous transport layer (PTL) anode 7 , the first opening 6 extending from the first side 4 to the opposite side of anode frame extends 4"
• the cathode frame 11 comprising the second side 5, a side of the cathode frame 5" opposite the second side 5 , and a second opening 9 for receiving the PTL cathode 10 , the second opening 9 extending from the second side 5 to the opposite side of the cathode frame 5" extends,
• the side of the anode frame 4" opposite the first side 4 and the side of the cathode frame 5 " opposite the second side 5 being arranged next to one another,
• wherein anode frame 8 and cathode frame 11 are connected to each other,
• the first opening 6 and the second opening 9 being connected to each other,
• wherein the first opening 6 is larger than the second opening 9 and wherein the anode frame 8 and the cathode frame 11 are arranged such that the side of the anode frame 4 " opposite the first side 4" and the side of the cathode frame 5" , opposite the second side 5" form a shoulder 12 at the transition from the anode frame 8 to the cathode frame 11 , the shoulder 12 being that part of the cathode frame 11 which adjoins the second opening 9 and frames the second opening 9 and the shoulder 12 has a planar third surface as a support surface for the Catalyst Coated Membrane (CCM) 13 , and wherein the anode frame 8 comprises a metal core 21 and a coating of a sealing material, e.g. a rubber coating 22 , and the cathode frame 11 comprises a metal core 21 and a coating of a sealing material , For example, a coating of rubber 22 includes. As Coating for the metal core 21 is any suitable sealing material, for example rubber, in particular ethylene-propylene-diene rubber (EPDM).

The subject matter of the invention is a frame 1 for a PEM electrolytic cell 2 with a metal core 21 , the metal core 21 being coated with a sealing material, preferably rubber, for example EPDM ( Figure 3a and 3b ). The metal offers good mechanical stability, whereas the coating of sealing material, preferably rubber, for example EPDM, produces the sealing effect. In that all or at least 90%, preferably at least 95% or more of the surface of the metal core 21 of the anode frame 8 or the entire or at least 90%, preferably at least 95% or more of the surface of the metal core 21 of the cathode frame 11 is coated with sealing material, preferably rubber, for example EPDM, the sealing surface is very large. Another advantage is that the components such as the PTL anode 7 and PTL cathode 10 can be pressed into the frame 1, in particular into the anode frame 8 and the cathode frame 11 (press fit) and thus into the PEM electrolytic cell 2 or the PEM electrolytic cell stack 23 in the case of electrolysis under high pressure or differential pressure, for example electrolysis which is carried out at a differential pressure of up to 40 bar, there is no deformation of the frame and no larger gap 17 is formed between individual components inside the frame 1 and between individual ones component and frame 1, e.g. between PTL cathode 10 and frame 1 and/or between PTL anode 7 and frame 1 ( figure 8 ). is formed.

The metal for the core of the anode frame 8 and/or cathode frame 11 can be, for example, high-grade steel, for example high-grade steel with a thickness of 0.5 cm. The coated anode frame 8 and/or coated cathode frame 11 can have a thickness of 7.5 cm, for example.

For example, the first opening 6 is at least 0.5 mm or 1 mm, for example 2 mm or more, 0.5 cm, preferably 1 cm, particularly preferably 1.5 cm or more larger than the second opening 9, with the shoulder 12 , which is formed inside the cathode frame 11 by the larger first opening 6 and the smaller second opening 9 , has the same width throughout ( Figure 7b ). Alternatively , paragraph 12 can be of different widths at different points. The width of the heel 12 and with it the planar third surface for receiving the CCM 13 may have the same or different widths at different locations.

The anode frame 8 can, for example, have external dimensions of 35 cm by 35 cm and the first opening can have dimensions of 20 cm by 20 cm. The cathode frame 11 can, for example, have external dimensions of 35 cm by 35 cm and the first opening can have dimensions of 21 cm by 21 cm ( Figure 9a and b ). The person skilled in the art is familiar with different frame shapes in which the frame 1, the anode frame 8 and the cathode frame 11 can be designed, for example square, rectangular, round.

In addition, the openings framing anode frame 8 and cathode frame 11 are of different sizes ( Figure 7b , 8th , 9a and 9b ). The cathode frame 11 is smaller and the anode frame 8 is larger. This means that the gas pressure that occurs in the cathode during PEM electrolysis does not or cannot press on the 'gap 17 between anode frame 8 and PTL anode 7 on the anode side, even with a high differential pressure, for example a differential pressure of 40 bar. The CCM 13 is therefore only pressed against the PTL anode 7 on the anode side and is well mechanically supported on the PTL anode 7 . A creeping 24 of the CCM 13 into the gap 17 between the anode frame 8 and the PTL anode 7 on the anode side can be prevented in this way.

In preferred embodiments, the frame 1 according to the invention comprises a channel or type I 14 for the supply and removal of water and gas and one or more channels type II 15, the channel type I 14 not having the first opening 6 in the anode frame 8 or the second Opening 9 in the cathode frame 11 are connected. In preferred embodiments of the frame 1 , the anode frame 8 comprises on the surface of the first side 4 one or more type II channels 15 which are connected to the type I channel 14 and which connect the type I channel 14 to the first opening 6 and which, when the frame 1 is installed in a PEM electrolytic cell 2 or a stack type PEM electrolytic device 23 , are arranged towards the BPP 16 and the side of the anode frame 4" opposite the first side 4 does not have type II channels 15. In preferred embodiments of the Frame 1 , the cathode frame 11 comprises on the surface of the second side 5 a type II duct 15 which is connected to one or more type I ducts 14 and connects the type I duct 14 to the second opening 9 and which, when the frame 1 in a PEM electrolytic cell 2 or a stack type PEM electrolytic device 23 , are arranged towards the BPP 16 and the side of the cathode frame 5" opposite the second side 5 does not have type II 15 channels.

In preferred embodiments, the frame 1 according to the invention comprises at least two type I ducts 14 for transporting water and gas in and out and at least two type II ducts 15 , the type I ducts 14 not having the first opening 6 in the anode frame 8 or the second opening 9 are connected in the cathode frame 11 . In preferred embodiments of the frame 1 , the anode frame 8 comprises on the surface of the first side 4 at least two type II channels 15 which are connected to the at least two type I channels 14 and which connect the type I channels 14 to the first opening 6 and the , when the frame 1 is installed in a PEM electrolytic cell 2 or a stack type PEM electrolytic device 23 , are arranged towards the BPP 16 and the side of the anode frame 4" opposite the first side 4 does not have type II channels 15. Preferably connecting several Type II channels 15 arranged on the first side 4 of the anode frame 7 , a type I channel 14 with the first opening 6. In preferred embodiments of the frame 1 , the cathode frame 11 on the surface of the second side 5 comprises at least two type II channels 15 which are connected to at least two type I ducts 14 and which connect the type I ducts 14 to the second opening 9 and which, when the frame 1 is installed in a PEM electrolytic cell 2 or a stacked type PEM electrolytic device 23 , towards the BPP 16 are arranged and wherein the side of the cathode frame 5 " opposite the second side 5" has no type II channels 15 . Preferably, a plurality of Type II channels 15 arranged on the second side 5 of the cathode frame 11 connect a Type I channel 14 to the second opening 9.

The channels type II 15 , the channels type I 14 with the first opening 6 and the second opening 9, ie in a PEM electrolytic cell the PTL anode 7 and the PTL cathode 10 with the channels type I 14 for transporting water in and out and gas connect are arranged in the anode frame 8 and/or in the cathode frame 11 so that they point towards the BPP 16 , and not towards the CCM 13. When gas and water flow through the type I channels 14 during electrolysis, will the CCM 13 is not affected by this, because the side of the anode frame 7 and the side of the cathode frame 11 on which the CCM 13 rests does not include any type II channels 15, ie no channels in the immediate vicinity of the first opening 6 or the second opening 9 in the area where the CCM 13 is arranged and subjected to a differential pressure of up to 40 bar during electrolysis. The CCM 13 rests on a smooth, level surface without channels and is therefore well supported even at a differential pressure of up to 40 bar. At the same time, the anode compartment (the anode compartment is formed by anode frame 7, CCM 13 and BPP 16), the cathode compartment (the cathode compartment is formed by cathode frame 11, CCM 13 and BPP 16) and the entire PEM electrolytic cell 2 also at a differential pressure of up to 40 bar fully sealed so no gas or water can escape.

In the frame 1 according to the invention, the anode frame 8 and the cathode frame 11 are connected to one another via connecting elements. Corresponding connecting elements are known to the person skilled in the art. In preferred embodiments of the frame 1 , the anode frame 8 comprises one or more connecting elements, for example pins 19 and the cathode frame 11 one or more connecting elements, for example holes 18, the pin or pins 19 and the hole or holes 18 being arranged such that the hole( s) 18 in the cathode frame 11 is plugged onto the pin(s) 19 in the anode frame 8 and the anode frame 8 and cathode frame 11 can thereby be connected to one another.

The invention relates to a PEM electrolytic cell 2 for operation under a differential pressure of up to 40 bar to generate high-pressure hydrogen, comprising a PEM membrane electrode arrangement with a CCM 13, a PTL anode 7, a PTL cathode 10, the PEM electrolytic cell 2 having a frame 1 comprises, wherein the first opening 6 in the anode frame 8 comprises the PTL anode 7 and the second opening 9 in the cathode frame 11 comprises the PTL cathode 10 and the CCM 13 between the side of the anode frame 4 " opposite the first side 4" and that of the second side 5 opposite side of the cathode frame 5" , with one side of the CCM 13 resting on the PTL anode 7 and the other side of the CCM 13 resting on the step 12 and the PTL cathode 10 ( Figure 7b and 7c ).

In preferred embodiments, the PEM electrolytic cell 2 according to the invention comprises a CCM 13 with a thickness of less than 80 μm, for example a CCM 13 with a thickness of 50 μm or less.

The coatings made of sealing material, for example the rubber coating 22, preferably the EPDM coating of the anode frame 8, the coatings made of sealing material, for example the rubber coating 22, preferably the EPDM coating of the cathode frame 11 and the Paragraph 12 together with the CCM 13 ( Figure 7c ) and seal the PEM electrolytic cell 2 and the anode compartment and the cathode compartment completely, without the CCM 13 creeping 24 into the gap 17 between the anode frame 8 and the PTL anode 7 . The special arrangement of the type II channels 15 ensures that water and gas is transported in and out completely, as well as the stability of the CCM 13 and complete sealing of the PEM electrolytic cell 2. The frame 1 according to the invention therefore enables the use of CCMs 13 with a thickness of less than 80 µm, for example with a thickness of 50 µm or less (=thin CCM 13). With the frame 1 according to the invention, PEM electrolytic cells 2 can be produced with a thinner CCM 13 than is usual in the prior art. In addition, these PEM electrolytic cells 2 can be operated in such a way that the hydrogen is accumulated to generate a differential pressure on the cathode side of up to 40 bar without the CCM 13 being damaged or the PEM electrolytic cell 2 becoming leaky.

• wobei der Anodenrahmen 8 eine erste Seite 4 mit planarer erster Oberfläche, eine der ersten Seite 4 gegenüberliegende Seite des Anodenrahmes 4" und eine erste Öffnung 6 zur Aufnahme der PTL Anode 7 umfasst, wobei die erste Öffnung 6 sich von der ersten Seite 4 bis zur der ersten Seite 4 gegenüberliegenden Seite des Anodenrahmens 4" erstreckt, und wobei die erste Öffnung 6 von dem Anodenrahmen 8 umgeben ist, und wobei der Anodenrahmen 8 mindestens ein Verbindungselement zur Verbindung mit dem Kathodenrahmen 11, beispielsweise einen Stift 19, umfasst,
• wobei der Kathodenrahmen 11 eine zweite Seite 5 mit planarer zweiter Oberfläche, eine der zweiten Seite 5 gegenüberliegende Seite des Kathodenrahmens 5" und eine zweite Öffnung 9 zur Aufnahme der PTL Kathode 10 umfasst, wobei die zweite Öffnung 9 sich von der zweiten Seite 5 bis zur der zweiten Seite 5 gegenüberliegenden Seite des Kathodenrahmens 5" erstreckt und von dem Kathodenrahmen 10 umgeben ist, und wobei der Kathodenrahmen 11 mindestens ein Verbindungselement zur Verbindung mit dem Anodenrahmen 8, beispielsweise ein Loch 18 zur Aufnahme des Stiftes 19 des Anodenrahmens 8, umfasst,
• wobei zwischen der ersten Seite 4 des Anodenrahmes 8 und der zweiten Seite 5 des Kathodenrahmens 11 die BPP 16 angeordnet ist,
• wobei der Anodenrahmen 8 einen Kern aus Metall 21 und eine Beschichtung aus Dichtwerkstoff, beispielsweise eine Beschichtung aus Gummi 22, vorzugsweise eine Beschichtung aus EPDM umfasst, und wobei die BPP 16 mit der PTL Anode 7 verbunden ist und die mit der PTL Anode 7 verbundene BPP 16 in die erste Öffnung 6 eingepresst und von dem Anodenrahmen 8 eingerahmt ist,
• der Kathodenrahmen 10 einen Kern aus Metall 21 und eine Beschichtung aus Dichtwerkstoff, beispielsweise eine Beschichtung aus Gummi 22, vorzugsweise eine Beschichtung aus EPDM umfasst und wobei die PTL Kathode 10 in die zweite Öffnung 9 eingepresst und von dem Kathodenrahmen 11 eingerahmt ist,
• wobei Anodenrahmens 8 und Kathodenrahmen 11 über die Verbindungselemente des Anodenrahmens 8 und des Kathodenrahmens 11 verbunden werden, beispielsweise der Stift 19 des Anodenrahmens 8 in dem Loch 18 des Kathodenrahmens 11 steckt und der Anodenrahmen 8 und Kathodenrahmen 11 dadurch miteinander verbunden sind,
• wobei die erste Öffnung 6 größer ist als die zweite Öffnung 9 und wobei der Anodenrahmen 8 und der Kathodenrahmen 11 so angeordnet sind, dass die erste Seite 4 und die zweite Seite 5 beim Übergang vom Anodenrahmen 8 zum Kathodenrahmen 11 einen Absatz 12 bilden, wobei der Absatz 12 der Teil des Kathodenrahmens 11 ist, der an die zweite Öffnung 9 angrenzt und die zweite Öffnung 9 einrahmt und wobei der Absatz 12 eine planare dritte Oberfläche als Auflagefläche für die CCM 13 bildet, wobei die BPP 16 auf der einen Seite auf der PTL Anode 7 und dem Anodenrahmen 8 aufliegt und auf der anderen Seite auf der PTL Kathode 10, dem Kathodenrahmen 11 und dem Absatz 12 aufliegt.

The subject matter of the invention is a preassembled subassembly 20 for producing an electrolysis device of the stack type 23 comprising an anode frame 8, a cathode frame 11, a BPP 16, a PTL anode 7 and a PTL cathode 10,

• wherein the anode frame 8 comprises a first side 4 with a planar first surface, a side of the anode frame 4" opposite the first side 4 , and a first opening 6 for receiving the PTL anode 7 , the first opening 6 extending from the first side 4 to the the side of the anode frame 4 " opposite the first side 4, and wherein the first opening 6 is surrounded by the anode frame 8 , and wherein the anode frame 8 comprises at least one connecting element for connection to the cathode frame 11, for example a pin 19 ,
• wherein the cathode frame 11 comprises a second side 5 with a planar second surface, a side of the cathode frame 5" opposite the second side 5 , and a second opening 9 for receiving the PTL cathode 10 , the second opening 9 extending from the second side 5 to the the second page 5 opposite side of cathode frame 5" and is surrounded by the cathode frame 10 , and wherein the cathode frame 11 comprises at least one connecting element for connection to the anode frame 8, for example a hole 18 for receiving the pin 19 of the anode frame 8,
• the BPP 16 being arranged between the first side 4 of the anode frame 8 and the second side 5 of the cathode frame 11 ,
• wherein the anode frame 8 comprises a core of metal 21 and a coating of sealing material, e.g. a coating of rubber 22, preferably a coating of EPDM, and wherein the BPP 16 is connected to the PTL anode 7 and the BPP is connected to the PTL anode 7 16 is pressed into the first opening 6 and framed by the anode frame 8 ,
• the cathode frame 10 comprises a metal core 21 and a coating of sealing material, for example a rubber coating 22, preferably an EPDM coating, and the PTL cathode 10 is pressed into the second opening 9 and framed by the cathode frame 11 ,
• wherein the anode frame 8 and cathode frame 11 are connected via the connecting elements of the anode frame 8 and the cathode frame 11 , for example the pin 19 of the anode frame 8 is inserted in the hole 18 of the cathode frame 11 and the anode frame 8 and cathode frame 11 are thereby connected to one another,
• wherein the first opening 6 is larger than the second opening 9 and wherein the anode frame 8 and the cathode frame 11 are arranged such that the first side 4 and the second side 5 form a shoulder 12 at the transition from the anode frame 8 to the cathode frame 11 , the Shoulder 12 is that part of the cathode frame 11 which abuts and frames the second opening 9 and the shoulder 12 forms a planar third surface as a support surface for the CCM 13 , with the BPP 16 on one side on the PTL Anode 7 and the anode frame 8 rests and on the other side on the PTL cathode 10, the cathode frame 11 and paragraph 12 rests.

1. a) für den Anodenrahmen 8 ein Kern aus Metall 21 hergestellt wird, wobei der Kern aus Metall 21 eine erste Seite 4 mit planarer erster Oberfläche und eine der ersten Seite 4 gegenüberliegende Seite des Anodenrahmens 4" umfasst, wobei die erste Seite 4 und die gegenüberliegende Seite des Anodenrahmens 4" eine erste Öffnung 6 umfassen, die sich von der ersten Seite 4 bis zur gegenüberliegenden Seite des Anodenrahmens 4" erstreckt und die von dem Anodenrahmen 8 eingerahmt ist, einen, zwei oder mehrere Kanäle Typ I 14 zum An- und Abtransport von Wasser und Gas umfassen, wobei der bzw. die Kanäle Typ I 14 nicht mit der ersten Öffnung 6 im Anodenrahmen 8 verbunden ist bzw. sind, und wobei der Anodenrahmen 8 mindestens ein Verbindungselement zur Verbindung mit dem Kathodenrahmen 11, z.B. einen Stift 19, umfasst,
2. b) mindestens 90 % der Oberfläche des gemäß a) hergestellten Kerns aus Metall 21 für den Anodenrahmen 8 mit Natur- oder Synthesekautschuk beschichtet und anschließend vulkanisiert werden und dadurch auf dem Kern aus Metall 21 eine Beschichtung aus Gummi 22, vorzugsweise eine Beschichtung aus EPDM erzeugt wird, wobei in der Beschichtung aus Gummi 22 ein, zwei oder mehrere Kanäle Typ II 15 auf der Oberfläche der ersten Seite 4 erzeugt werden, die mit einem, zwei oder mehreren Kanälen Typ I 14 verbunden sind und die den bzw. die Kanäle Typ I 14 mit der ersten Öffnung 6 verbinden und die, wenn der Anodenrahmen 8 in einer PEM Elektrolysezelle 2 oder einer PEM Elektrolysevorrichtung vom Stapeltyp 23 eingebaut ist, in Richtung zur BPP 16 angeordnet sind und wobei in der der ersten Seite 4 gegenüberliegenden Seite des Anodenrahmens 4" keine Kanäle Typ II 15 erzeugt werden,
3. c) in den gemäß a) und b) hergestellten Anodenrahmen 8 die PTL Anode 7 und die BPP 16 gelegt oder eingepresst werden,
4. d) für den Kathodenrahmen 11 ein Kern aus Metall 21 hergestellt wird, wobei der Kern aus Metall 21 eine zweite Seite 5 mit planarer zweiter Oberfläche und eine der zweiten Seite 5 gegenüberliegende Seite des Kathodenrahmens 5" umfasst, wobei die zweite Seite 5 und die gegenüberliegende Seite des Kathodenrahmens 5" eine zweite Öffnung 9 umfassen, die sich von der zweiten Seite 5 bis zur gegenüberliegenden Seite des Kathodenrahmens 5" erstreckt und die von dem Kathodenrahmen 11 eingerahmt ist, einen, zwei oder mehrere Kanäle Typ I 14 zum An- und Abtransport von Wasser und Gas umfasst, wobei der bzw. die Kanäle Typ I 14 nicht mit der zweiten Öffnung 9 im Kathodenrahmen 11 verbunden sind, und wobei der Kathodenrahmen 11 mindestens ein Verbindungselement zur Verbindung mit dem Anodenrahmen 8, z.B. ein Loch 18, umfasst,
5. e) mindestens 90 % der Oberfläche des gemäß d) hergestellten Kerns aus Metall 21 für den Kathodenrahmen 11 mit Natur- oder Synthesekautschuk beschichtet und anschließend vulkanisiert werden und dadurch auf dem Kern aus Metall 21 eine Beschichtung aus Gummi 22, vorzugsweise eine Beschichtung aus EPDM erzeugt wird, wobei in der Beschichtung aus Gummi 22 ein, zwei oder mehrere Kanäle Typ II 15 auf der Oberfläche der zweiten Seite 5 erzeugt werden, die mit einem, zwei oder mehreren Kanälen Typ I 14 verbunden sind und der bzw. die den bzw. die Kanäle Typ I 14 mit der zweiten Öffnung 9 verbinden und die, wenn der Kathodenrahmen 11 in einer PEM Elektrolysezelle 2 oder einer PEM Elektrolysevorrichtung vom Stapeltyp 23 eingebaut ist, in Richtung zur BPP 16 angeordnet sind und wobei in der der zweiten Seite 5 gegenüberliegenden Seite des Kathodenrahmens 5" keine Kanäle Typ II 15 erzeugt werden,
6. f) der gemäß d) und e) hergestellte Kathodenrahmen 11 mit dem Anodenrahmen 8 verbunden wird, beispielsweise dadurch, dass der Kathodenrahmen 11 auf den Anodenrahmen 8 aufgesteckt wird und wobei die BPP 16 zwischen der erste Seite 4 und der zweiten Seite 5 angeordnet ist und dann die PTL Kathode 10 in den Kathodenrahmen 11 eingelegt oder eingepresst wird.

The subject matter of the invention is also a method for producing a preassembled module 20, comprising the method steps

1. a) a metal core 21 is produced for the anode frame 8 , the metal core 21 comprising a first side 4 with a planar first surface and a side of the anode frame 4 " opposite the first side 4, the first side 4 and the opposite Side of the anode frame 4 " comprise a first opening 6 , which extends from the first side 4 to the opposite side of the anode frame 4" and which is framed by the anode frame 8 , one, two or more channels type I 14 for transport of water and gas, the type I channel(s ) 14 not being connected to the first opening 6 in the anode frame 8 , and the anode frame 8 having at least one connecting element for connection to the cathode frame 11, e.g. a pin 19, includes,
2. b) at least 90% of the surface of the metal core 21 produced according to a) for the anode frame 8 is coated with natural or synthetic rubber and then vulcanized, thereby producing a rubber coating 22 on the metal core 21 , preferably an EPDM coating is created in the coating of rubber 22 one, two or more channels type II 15 on the surface of the first side 4 , which are connected to one, two or more channels type I 14 and which the channel or channels type I 14 to the first opening 6 and which, when the anode frame 8 is installed in a PEM electrolytic cell 2 or a stacked type PEM electrolytic device 23 , are arranged towards the BPP 16 and wherein in the opposite side of the first side 4 of the anode frame 4" no type II 15 channels are generated,
3. c) the PTL anode 7 and the BPP 16 are placed or pressed into the anode frame 8 produced according to a) and b),
4. d) a metal core 21 is produced for the cathode frame 11 , the metal core 21 comprising a second side 5 with a planar second surface and a side of the cathode frame 5 " opposite the second side 5, the second side 5 and the opposite Side of the cathode frame 5 " comprise a second opening 9 , which extends from the second side 5 to the opposite side of the cathode frame 5" and which is framed by the cathode frame 11 , one, two or more channels type I 14 for supply and removal of water and gas, the channel or channels type I 14 are not connected to the second opening 9 in the cathode frame 11 , and wherein the cathode frame 11 comprises at least one connecting element for connection to the anode frame 8, e.g. a hole 18 ,
5. e) at least 90% of the surface of the metal core 21 for the cathode frame 11 produced according to d) is coated with natural or synthetic rubber and then vulcanized, thereby producing a rubber coating 22 on the metal core 21 , preferably an EPDM coating is created in the coating of rubber 22 one, two or more channels type II 15 on the surface of the second side 5 , which are connected to one, two or more channels type I 14 and the or the or the Type I ducts 14 connecting to the second opening 9 and which, when the cathode frame 11 is installed in a PEM electrolytic cell 2 or a stacked type PEM electrolytic device 23 , are arranged towards the BPP 16 and being in the opposite side of the second side 5 of the cathode frame 5" no channels type II 15 are generated,
6. f) the cathode frame 11 produced according to d) and e) is connected to the anode frame 8 , for example by the cathode frame 11 being pushed onto the anode frame 8 and the BPP 16 being arranged between the first side 4 and the second side 5 and then the PTL cathode 10 is inserted or pressed into the cathode frame 11 .

1. a) mindestens x vorassemblierte Baugruppen 20 und mindestens x+1 CCMs 13 werden abwechselnd übereinander gestapelt, wobei ein Stapel vorassemblierter Baugruppen 3 erzeugt wird, wobei in dem Stapel vorassemblierter Baugruppen 3 jeweils eine vorassemblierte Baugruppe 20 und eine CCM 13 abwechselnd übereinander gestapelt sind und wobei auf der Oberseite und der Unterseite des Stapels vorassemblierter Baugruppen 3 jeweils eine CCM 13 und zwischen zwei benachbarten vorassemblierten Baugruppen 20 jeweils eine CCM 13 angeordnet ist, und wobei
2. b) dann auf der einen Seite des Stapels vorassemblierter Baugruppen 3 eine einzelne Anode parallel zu einer äußeren CCM 13 angeordnet wird und auf der anderen Seite des Stapels vorassemblierter Baugruppen 3 eine einzelne Kathode parallel zu einer äußeren CCM 13 angeordnet wird,
3. c) parallel zu der einzelnen Anode und parallel zu der einzelnen Kathode jeweils eine Endplatte angeordnet und der erzeugte Stapel dann zwischen den zwei Endplatten zu einer PEM Elektrolysevorrichtung vom Stapeltyp 23 zusammengepresst wird,

wobei jede der x+1 CCMs 13 in der PEM Elektrolysevorrichtung vom Stapeltyp 23 eine Dicke von weniger als 80 µm hat und wobei x eine ganze Zahl und ≥ 2 ist.The invention also relates to a method for producing a stack-type PEM electrolysis device 23 for operation under differential pressure for generating high-pressure hydrogen, comprising the method steps,

1. a) at least x preassembled assemblies 20 and at least x+1 CCMs 13 are stacked alternately on top of one another, a stack of preassembled assemblies 3 being produced, with a preassembled assembly 20 and a CCM 13 being stacked alternately on top of one another in the stack of preassembled assemblies 3 and wherein on the upper side and the lower side of the stack of preassembled assemblies 3 each have a CCM 13 and between two adjacent preassembled assemblies 20 each have a CCM 13 , and wherein
2. b) then on one side of the stack preassembled assemblies 3 a single anode is placed parallel to an outer CCM 13 and on the on the other side of the stack of preassembled assemblies 3 , a single cathode is placed parallel to an outer CCM 13 ,
3. c) an end plate is arranged parallel to the individual anode and parallel to the individual cathode and the stack produced is then compressed between the two end plates to form a stack-type PEM electrolysis device 23 ,

each of the x+1 CCMs 13 in the stack-type PEM electrolyzer 23 has a thickness of less than 80 µm and x is an integer and ≥2.

The invention relates to a stack-type PEM electrolysis device 23 for operation under differential pressure to produce high-pressure hydrogen, comprising x preassembled assemblies 20, x+1 CCMs 13, a single anode, a single cathode and two end plates, the x preassembled assemblies 20 and the x+1 CCMs 13 are stacked alternately on top of each other to form a stack of preassembled assemblies 3 , with a preassembled assembly 20 and a CCM 13 being stacked alternately on top of each other in the stack of preassembled assemblies 3 and with the top and bottom of the stack of preassembled assemblies 3 one CCM 13 is arranged in each case and one CCM 13 is arranged between two adjacent preassembled assemblies 20 , and a single anode is arranged parallel to an outer CCM 13 on one side of the stack of preassembled assemblies 3 and on the other side of the stack of preassembled assemblies 3 a single cathode is placed parallel to an outer CCM 13 , with one end plate each placed parallel to the single anode and parallel to the single cathode, and the stack produced is compressed between the two end plates into a stack-type PEM electrolyzer 23 , each of the x+1 CCMs 13 in the stack-type PEM electrolyzer 23 have a thickness of less than 80 µm, preferably a thickness of less than 50 µm or less, and where x is an integer and ≥2.

In the PEM electrolysis device of the stack type 23 , other components can be installed at the appropriate points as required, for example an insulating plate can be installed between the CCM 13 and the end plate. Insulating plates at these points, for example, prevent the end plates from being short-circuited, for example when using screws. Appropriate Components are known to those skilled in the art. Those skilled in the art can adjust the manufacturing process accordingly.

The invention also relates to a stack-type PEM electrolysis device 23 for operation under differential pressure to generate high-pressure hydrogen, comprising x preassembled assemblies 20, x+1 CCMs 13, a single anode, a single cathode and two end plates, the x preassembled assemblies 20 and the x+1 CCMs 13 are stacked alternately on top of one another to form a stack of preassembled assemblies 3 , with a preassembled assembly 20 and a CCM 13 being stacked alternately on top of one another in the stack of preassembled assemblies 3 and on the top and bottom of the stack of preassembled assemblies 3 each has a CCM 13 and between two adjacent preassembled assemblies 20 each a CCM 13 is arranged, and wherein on one side of the stack of preassembled assemblies 3 a single anode is arranged parallel to an outer CCM 13 and on the other side of the stack of preassembled assemblies 3 a single cathode is placed in parallel with an outer CCM 13 , with one end plate each placed parallel to the single anode and parallel to the single cathode, and the stack produced is compressed between the two end plates into a stack-type PEM electrolyzer 23 , each of the x+1 CCMs 13 in the stack-type PEM electrolyzer 23) has a thickness of less than 80 µm and where x is an integer and ≥2.

In preferred embodiments, the PEM electrolysis device of the stack type 23 comprises at least 2 or 3 or 5 or more, for example 10, 50, 100, 500, 1000 or more preassembled components 20. Preferably, the PEM electrolysis device of the stack type 23 according to the invention comprises a number of x preassembled ones Assemblies 20, where x is an integer and ≥ 2, a cathode frame 11, a CCM 13, an anode frame 8 and two end plates. In the stack-type PEM electrolytic device 23 of the present invention, it is preferable that the first and last PEM electrolytic cells 2 are different from those in between. For example, to manufacture a stack type PEM electrolytic device 23 , a CCM 13 is placed on a cathode frame 11 , on the CCM 13 x preassembled assemblies 20 and x CCMs 13 are stacked alternately, and then a Anode frame 8. The stack is pressed between end plates into a stack type PEM electrolyzer 23 where x is an integer and ≥2.

Another advantage of the invention is cost. The type II channels 15 are not milled out of each anode frame 8 and each cathode frame 11 , but are transferred once into a tool. One tool is the negative of the anode frame 8, another tool is the negative of the cathode frame 11. The type II channels 15 are transferred to the tool and inserted like a stamp into the sealing material, preferably the rubber, for example EPDM. With the aid of the tool, the metal core 21 is coated with the sealing material, preferably rubber, for example EPDM, by vulcanization, with the channels type II 15 being simultaneously produced in the regions of the anode frame 8 and/or the cathode frame 11 desired according to the invention. The molded parts or molded rubber parts produced by vulcanization of anode frame 8 and/or cathode frame 11 can be used directly and can be produced in large numbers at low cost.

The stack-type PEM electrolyzer 23 is preferably designed so that all components have a smooth and homogeneous surface, so that no voltage peaks occur on the CCM 13 . In order to prevent the CCM 13 from creeping 24 into the pores of the PTL anode 7 and/or the PTL cathode 10 under gas pressure, PTL anodes 7 and/or PTL cathodes 10 with a pore diameter <0.1 mm are used, for example. For example, as PTL anode 7 and/or PTL cathode 10 , PTLs with a so-called “microporous layer”, ie a particularly homogeneous surface, can be used.

The anode frame 8 and the cathode frame 11 can easily be joined together to form a preassembled assembly 20 , since the seal and the anode frame 8 or the seal and the cathode frame 11 each consist of one component. A BPP 16, which is connected to a PTL anode 7 , is preferably used to produce a preassembled assembly 20 . For example, BPP 16 and PTL anode 7 are welded so that BPP 16 and PTL anode 7 are present as one component. The anode frame 8 is first pressed onto the BPP 16 and the PTL anode 7 . For example, the anode frame 8 can additionally have a second pin that can be inserted into the BPP 16 . Then the anode frame 8 is turned over with the pressed-in PTL anode 7 and the BPP 16 and the cathode frame 11 can also be inserted on the other side of the anode frame 8 . Then the PTL cathode 10 is inserted into the cathode frame 11 ( figure 6 ). A preassembled module 20 is obtained. Preassembled assemblies 20 can then be stacked alternately with CCMs 13 via centering pins, for example, in order to produce stacks of preassembled assemblies 3 or PEM electrolysis devices of the stack type 23 . Reference sign Frame 1 PEM electrolysis cell 2 Stack of pre-assembled assemblies 3 First side of frame 4 The side of the anode frame 8 opposite the first side 4 4" Second page 5 The side of the cathode frame 11 opposite the second side 5 5" First opening 6 Porous transport layer (PTL) anode 7 anode frame 8th Second opening 9 Porous transport layer (PTL) cathode 10 cathode frame 11 Unit volume 12 Catalyst Coated Membrane (CCM) 13 Type I channel 14 Type II canal 15 Bipolar Plate (BPP) 16 gap 17 Hole 18 Pen 19 Pre-assembled assembly 20 metal core 21 Rubber coating 22 Stack type PEM electrolyzer 23 Crawl 24

• Figur 1: Klassischer Aufbau einer PEM Elektrolysezelle aus dem Stand der Technik mit Rahmen 1, katalysatorbeschichteter Membran (CCM) 13, Bipolarplatte (BPP) 16, PTL Anode 7, PTL Kathode 10 mit Spalt 17 zwischen Rahmen 1 und PTL Anode 7 und Rahmen 1 und PTL Kathode 10.
• Figur 2: Rahmen 1 gemäß Figur 1 mit Verformung des Rahmens 1 und Bildung eines größeren Spalts 17 zwischen Rahmen 1 und PTL Anode 7 und Rahmen 1 und PTL Kathode 10 und Kriechen 24 der CCM 13 in den vergrößerten Spalt 17 zwischen Rahmen 1 und PTL Anode 7 und Rahmen 1 und PTL Kathode 10.
• Figur 3a: Erfindungsgemäßer Rahmen 1 umfassend einen Kern aus Metall 21, eine Beschichtung aus Gummi 22 und in der Beschichtung aus Gummi 22 einen Kanal Typ 2 15.
• Figur 3b: Erfindungsgemäßer Rahmen 1 umfassend einen Kern aus Metall 21, eine Beschichtung aus Gummi 22 und Teil eines Kanals Typ II 15 in der Beschichtung aus Gummi 22.
• Figur 4: Erfindungsgemäßer Kathodenrahmen 11 mit zweiter Öffnung 9, zwei Löchern 18 als Verbindungselement zur Verbindung mit dem Anodenrahmen 8, zwanzig Kanälen Typ I 14 und mehreren Kanälen Typ II 15 auf der zweiten Seite 5, die die zweite Öffnung 9 mit zehn Kanälen Typ I 14 verbinden.
• Figur 5: Erfindungsgemäßer Anodenrahmen 8 mit erster Öffnung 6, zwei Stiften 19 als Verbindungselement zur Verbindung mit dem Kathodenrahmen 11, zwanzig Kanälen Typ I 14 und mehreren Kanälen Typ II 15 auf der ersten Seite 4, die die erste Öffnung 6 mit zehn Kanälen Typ I 14 verbinden.
• Figur 6: Verfahren zur Herstellung einer vorassemblierten Baugruppe 20 mit den Verfahrensschritten a) Ausgangslage: PTL Anode 7 und BPP 16 sind verbunden (7 + 16), b) 1. Schritt: Stift 19 des Anodenrahmens 8 werden in die Löcher 19 der BPP 16 eingesteckt, c)2. Schritt: Umdrehen der Anordnung aus b), d)3. Schritt: Kathodenrahmen 11 in die Anordnung einstecken, e) 4. Schritt: PTL Kathode 10 in die zweite Öffnung 9 einlegen.
• Figur 7a: Vorassemblierte Baugruppe 20. Zu sehen sind alle 4 Teile, die zu der vorassemblierten Baugruppe 20 gehören: die Kathodenrahmen 11, Anodenrahmen 8 und die BPP/PTL Anode (7+16), und die PTL Kathode 10. Einmal als Explosionsdarstellung und einmal als zusammengesetztes Teil.
• Figur 7b: Vorassemblierte Baugruppe 20 in der Seitenansicht.
• Figur 7c: Vergrößerter Ausschnitt der vorassemblierten Baugruppe 20 mit dem Absatz 12.
• Figur 8: Gezeigt ist ein Ausschnitt eines schematischen Aufbaus einer erfindungsgemäßen Elektrolysevorrichtung vom Stapeltyp 23, der die Anordnung eines Stapels mit drei PEM Elektrolysezellen 2 zeigt. Der Ausschnitt umfasst einen Kathodenrahmen 11 mit PTL Kathode 10, einen Stapel von zwei vorassemblierten Baugruppen 20 und einen Anodenrahmen 8 mit PTL Anode 7.Die Pfeile zeigen die Richtung des Gasdrucks bei einer Hochdruck-Wasserstoffelektrolyse, die unter Differenzdruck von 40 bar durchgeführt wird.
• Figur 9: Beispielhafte Abmessungen für einen Kathodenrahmen 11 und einen dazu passenden Anodenrahmen 8.

Characters:

• figure 1 : Classic prior art PEM electrolytic cell design with frame 1, catalyst coated membrane (CCM) 13, bipolar plate (BPP) 16, PTL Anode 7, PTL cathode 10 with gap 17 between frame 1 and PTL anode 7 and frame 1 and PTL cathode 10.
• figure 2 : frame 1 according to figure 1 with deformation of frame 1 and formation of a larger gap 17 between frame 1 and PTL anode 7 and frame 1 and PTL cathode 10 and creeping 24 of the CCM 13 into the enlarged gap 17 between frame 1 and PTL anode 7 and frame 1 and PTL cathode 10 .
• Figure 3a : Frame 1 according to the invention comprising a metal core 21, a rubber coating 22 and in the rubber coating 22 a channel type 2 15.
• Figure 3b : Frame 1 according to the invention comprising a metal core 21, a rubber coating 22 and part of a type II channel 15 in the rubber coating 22.
• figure 4 : Cathode frame 11 according to the invention with second opening 9, two holes 18 as a connecting element for connection to the anode frame 8, twenty channels type I 14 and several channels type II 15 on the second side 5 connecting the second opening 9 with ten channels type I 14 .
• figure 5 : Anode frame 8 according to the invention with first opening 6, two pins 19 as a connecting element for connection to the cathode frame 11, twenty channels type I 14 and several channels type II 15 on the first side 4 connecting the first opening 6 with ten channels type I 14 .
• figure 6 : Process for the production of a preassembled module 20 with the process steps a) Initial situation: PTL anode 7 and BPP 16 are connected (7 + 16), b) 1st step: Pin 19 of the anode frame 8 is inserted into the holes 19 of the BPP 16 , c)2. Step: turning over the arrangement from b), d)3. Step: Insert the cathode frame 11 into the arrangement, e) 4th step: Insert the PTL cathode 10 into the second opening 9 .
• Figure 7a : Pre-assembled assembly 20. You can see all 4 parts that belong to the pre-assembled assembly 20 : the cathode frame 11, anode frame 8 and the BPP/PTL anode (7+16), and the PTL cathode 10. Once as an exploded view and once as a composite part.
• Figure 7b : Preassembled assembly 20 in side view.
• Figure 7c : Enlarged section of the pre-assembled assembly 20 with paragraph 12.
• figure 8 1: A section of a schematic structure of an electrolysis device of the stack type 23 according to the invention is shown, which shows the arrangement of a stack with three PEM electrolysis cells 2 . The section includes a cathode frame 11 with PTL cathode 10, a stack of two preassembled assemblies 20 and an anode frame 8 with PTL anode 7. The arrows show the direction of the gas pressure in a high-pressure hydrogen electrolysis, which is carried out under a differential pressure of 40 bar.
• figure 9 : Exemplary dimensions for a cathode frame 11 and a matching anode frame 8.

Claims (10)

Frame (1) for a PEM electrolytic cell (2) for a stack-type PEM electrolytic device (23), the frame (1) having a first side (4) with a planar first surface and a second side (4) opposite the first side (4 ) 5) having a planar second surface and comprising an anode frame (8) and a cathode frame (11) , and wherein the anode frame comprises the first side (4), a side of the anode frame (4") opposite the first side (4) and a first opening (6) for receiving the porous transport layer (PTL) anode (7) , the first opening (6) extends from the first side (4) to the opposite side of the anode frame (4") , wherein the cathode frame (11) comprises the second side (5), a side of the cathode frame (5" ) opposite the second side (5) and a second opening (9) for receiving the PTL cathode (10) , the second opening ( 9) extends from the second side (5) to the opposite side of the cathode frame (5") , the side of the anode frame (4 ") opposite the first side (4) and the side of the cathode frame (5 " ) opposite the second side (5) being arranged next to one another, the anode frame (8) and cathode frame (11) being connected to one another, the first opening (6) and the second opening (11) being connected to one another, characterized in that the first opening (6) is larger than the second opening (9) and the anode frame (8) and the cathode frame (11) are arranged in such a way that the side of the anode frame (4 ") and the side of the cathode frame (5 " ) opposite the second side (5) form a step (12) at the transition from the anode frame (8) to the cathode frame (11) , the step (12) being the part of the cathode frame (11 ) adjoining the second opening (9) and framing the second opening (9) and wherein the shoulder (12) forms a planar third surface as a support surface for the catalyst-coated membrane (CCM) (13) , and wherein the Anode frame (8) has a metal core (21) and a coating of sealing material, e.g. a coating of rubber (22) and wherein the cathode frame (11) comprises a core of metal (21) and a coating of sealing material, e.g. a coating of rubber (22) . Frame (1) according to Claim 1, comprising one or more Type I channels (14) for the supply and removal of water and gas and comprising one or more Type II channels (15), the Type I channels (14) not being connected to the first opening (6) in the anode frame (8) or the second opening (9) in the cathode frame (11) , characterized in that the anode frame ( 8) has one or more type II (15th ) which are connected to one or more type I ducts (14) and connect the type I duct(s ) (14) to the first opening (6) and which, when the frame (1) is placed in a PEM electrolytic cell (2 ) or a stack type PEM electrolyzer (23) , are arranged towards the bipolar plate (BPP) (16) and wherein the side of the anode frame (4" ) opposite the first side (4) does not have type II channels (15). . Frame (1) according to claim 1 or 2 comprising one or more channels type I (14) for the supply and removal of water and gas and comprising one or more channels type II (15), the channels type I (14) not including the first opening (6) in the anode frame (8) or the second opening (9) in the cathode frame (11) , characterized in that the cathode frame (11) on the surface of the second side (5) has one or more type II (15) connected to one or more type I ducts (14) and connecting the type I duct(s) (14) to the second opening (9) and which when the frame (1) is in a PEM electrolytic cell (2) or a stack type PEM electrolyser (23) , are arranged towards the bipolar plate (BPP) (16) and wherein the side of the cathode frame (5" ) opposite the second side (5) has no type II (15 ) has. Frame (1) according to any one of the preceding claims, wherein the anode frame (8) comprises one or more connecting elements for connection to the cathode frame (11) , for example one or more pins (19) and the cathode frame (11) one or more connecting elements for connection with the anode frame (8) , for example one or more holes (18), the connecting elements being arranged in such a way that the anode frame (8) and cathode frame (11) can be connected to one another, for example the pin or pins (19) and the or the holes (18) are arranged in such a way that the hole or holes (18) in the cathode frame (11) are placed on the pin or pins (19) in the anode frame (8) and the anode frame (8) and cathode frame (11 ) can be connected to each other. PEM electrolytic cell (2) for operation under differential pressure of up to 40 bar to generate high-pressure hydrogen, comprising a CCM (13), a PTL anode (7), a PTL cathode (10), characterized in that the PEM electrolytic cell (2 ) comprises a frame (1) according to any one of claims 1 to 4,
wherein the first opening (6) in the anode frame (8) comprises the PTL anode (7) and the second opening (9) in the cathode frame (11) comprises the PTL cathode (10) and the CCM (13) between the first side (4) opposite side of the anode frame (4") and the second side (5) opposite side of the cathode frame (5") , with one side of the CCM (13) resting on the PTL anode (7) and the other side of the CCM (13) rests on the shoulder (12) and the PTL cathode (10) . PEM electrolytic cell according to Claim 5, characterized in that the CCM (13) has a thickness of less than 80 µm, for example 50 µm or less. Preassembled subassembly (20) for manufacturing a stack-type electrolysis device (23) comprising an anode frame (8), a cathode frame (11), a BPP (16), a PTL anode (7) and a PTL cathode (10), wherein the anode frame (8) comprises a first side (4) with a planar first surface, a side of the anode frame (4 " ) opposite the first side (4) and a first opening (6) for receiving the PTL anode (7) , wherein the first opening (6) extends from the first side (4) to the opposite side of the anode frame (4") from the first side (4) , and wherein the first opening (6) is framed by the anode frame (8) , and wherein the anode frame (8) comprises at least one connecting element, preferably a pin (19) for connection to the cathode frame (11) , wherein the cathode frame (11) comprises a second side (5) with a planar second surface, a side of the cathode frame (5" ) opposite the second side (5) and a second opening (9) for receiving the PTL cathode (10) , wherein the second opening (9) extends from the second side (5) to the side of the cathode frame (5") opposite the second side (5) and is framed by the cathode frame (10) , and wherein the cathode frame (11) has at least one Connecting element, preferably comprising a hole (18) for receiving the pin (19), for connection to the anode frame (8) , the BPP (16) being arranged between the first side (4) and the second side (5) , characterized in that the anode frame (8) comprises a core of metal (21) and a coating of sealing material, preferably rubber (22) , and wherein the BPP (16) is bonded to the PTL anode (7) and the BPP (16 ) connected to the PTL anode (7 ) is pressed into the first opening (6) and framed by the anode frame (8) , the cathode frame (10) comprises a metal core (21) and a coating of a sealing material, preferably a rubber coating (22) , and the PTL cathode (10) is pressed into the second opening (9) and separated from the cathode frame (11 ) is framed, wherein the connecting element of the anode frame (8) is connected to the connecting element of the cathode frame (11) , preferably the at least one pin (19) in the at least one hole (18) and the anode frame (8) and cathode frame (11) are thereby connected to each other, wherein the first opening (6) is larger than the second opening (9) and wherein the anode frame (8) and the cathode frame (11) are arranged so that the first side (4) and the second side (5) at the transition from anode frame (8) form a step (12) to the cathode frame ( 11), the step (12) being that part of the cathode frame (11) which adjoins the second opening (9) and frames the second opening (9) and wherein the shoulder (12) forms a planar third surface as a support surface for the CCM (13) , the BPP (16) resting on one side on the PTL anode (7) and the anode frame (8) and on the other side on the PTL cathode (10), the cathode frame (11) and the paragraph (12) rests. Method for producing a preassembled module (20), comprising the method steps a) a metal core (21) is produced for the anode frame (8) , the metal core (21) having a first side (4) with a planar first surface and a side of the anode frame (4 ") wherein the first side (4) and the opposite side of the anode frame (4") include a first opening (6) extending from the first side (4) to the opposite side of the anode frame (4") and framed by the anode frame (8) , one or more type I channels (14) for transporting water and gas in and out, the type I channels (14) not being connected to the first opening (6) in the anode frame (8) are connected, and wherein the anode frame (8) comprises at least one connecting element, preferably at least one pin (19), for connection to the cathode frame (11) , b) at least 90% of the surface of the metal core (21) for the anode frame (8) produced in accordance with a) is coated with natural or synthetic rubber and then vulcanized and a rubber coating (22 ) is generated, wherein in the coating of rubber (22) one or more channels type II (15) are generated on the surface of the first side (4) with a or more type I channels (14) are connected and which connect the channel or channels type I (14) to the first opening (6) and when the anode frame (8) in a PEM electrolytic cell (2) or a PEM electrolytic device of the stack type (23) is installed, are arranged towards the BPP (16) and wherein no channels type II (15) are created in the opposite side of the first side (4) of the anode frame (4") , c) the PTL anode (7 ) is placed or pressed into the anode frame (8) produced according to a) and b), the PTL anode (7) being connected to a BPP (16) , d) a metal core (21) is produced for the cathode frame (11) , the metal core (21) having a second side (5) with a planar second surface and a side of the cathode frame (5 ") , wherein the second side (5) and the opposite side of the cathode frame (5") comprise a second opening (9) extending from the second side (5) to the opposite side of the cathode frame (5") and which is framed by the cathode frame (11) , comprises one or more type I channels (14) for transporting water and gas in and out, the type I channels (14) not being connected to the second opening (9) in the cathode frame (11 ) are connected, and wherein the cathode frame (11) comprises at least one connecting element, for example at least one hole (18) for connection to the anode frame (8) , e) at least 90% of the surface of the metal core (21) for the cathode frame (11) produced in accordance with d) is coated with natural or synthetic rubber and then vulcanized and a rubber coating (22 ) is created, creating in the coating of rubber (22) one or more channels type II (15) on the surface of the second side (5) , which are connected to one or more channels type I (14) and which den or connecting the type I channels (14) to the second opening (9) and which, when the cathode frame (11) is installed in a PEM electrolytic cell (2) or a stacked type PEM electrolytic device (23) , in are arranged in the direction of the BPP (16) and wherein no type II channels (15) are produced in the side of the cathode frame (5" ) opposite the second side (5) , f) the cathode frame (11) produced according to d) and e) by means of the at least one connecting element of the cathode frame (11), preferably the at least one hole (19) with the anode frame (8) produced according to a) to c) by means of the at least one connecting element of the anode frame (8), preferably the at least one pin (18), preferably the at least one hole (19) is placed on the at least one pin (18) and the cathode frame (11) is thereby connected to the anode frame (8). is, wherein the BPP (16) is arranged between the first side (4) and the second side (5) , and the PTL cathode (10) is inserted or pressed into the cathode frame (11) . Method for producing a stack-type PEM electrolysis device (23) for operation under differential pressure for generating high-pressure hydrogen, comprising the method steps, a) at least x preassembled assemblies (20) and at least x+1 CCMs (13) are stacked alternately on top of one another, a stack of preassembled assemblies (3) being produced, with one preassembled assembly (20) each being in the stack of preassembled assemblies (3) and a CCM (13) are alternately stacked one on top of the other, with one CCM (13 ) each being arranged on the top and bottom of the stack of preassembled assemblies (3) and one CCM (13) each being arranged between two adjacent preassembled assemblies (20 ) , and whereby b) a single anode is then arranged in parallel with an outer CCM (13 ) on one side of the stack of preassembled assemblies (3) and a single cathode is arranged in parallel with an outer CCM (13 ) on the other side of the stack of preassembled assemblies ( 3) is arranged c) an end plate is arranged parallel to the individual anode and parallel to the individual cathode and the stack produced is then between the two end plates is pressed together into a stack type PEM electrolyzer (23) , wherein each of the x+1 CCMs (13) in the stack-type PEM electrolyzer (23) has a thickness of less than 80 µm and wherein x is an integer and ≥ 2. Stack-type PEM electrolyzer (23) operating under differential pressure to produce high pressure hydrogen comprising x preassembled assemblies (20), x+1 CCMs (13), a single anode, a single cathode and two end plates, the x preassembled assemblies ( 20) and the x+1 CCMs (13) are stacked alternately on top of one another to form a stack of preassembled assemblies (3 ) , a preassembled assembly (20) and a CCM (13) being stacked alternately on top of one another in the stack of preassembled assemblies (3). and wherein one CCM (13) each is arranged on the upper side and the underside of the stack of preassembled assemblies (3) and one CCM (13) is arranged between two adjacent preassembled assemblies (20) , and wherein on one side of the stack of preassembled assemblies ( 3) a single anode is arranged parallel to an outer CCM (13) and on the other side of the stack of preassembled assemblies (3) a single cathode is arranged parallel to an outer CCM (13) ,
wherein an end plate is arranged parallel to the single anode and parallel to the single cathode respectively, and the stack produced is compressed between the two end plates into a stack-type PEM electrolyzer (23) , each of the x+1 CCMs (13) in the PEM Stack-type electrolyzer (23) has a thickness of less than 80 µm and x is an integer and ≥ 2

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