GB2625321A

GB2625321A - Manifold assembly for electrolyser

Info

Publication number: GB2625321A
Application number: GB2218816.3A
Authority: GB
Inventors: Francis Geary Paul
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-12-14
Filing date: 2022-12-14
Publication date: 2024-06-19
Also published as: GB202218816D0; WO2024126350A1

Abstract

The present invention relates to a manifold assembly 204 and associated electrolyser 202, where the electrolyser may generate hydrogen from water. The manifold assembly 204 comprises a housing block with at least one integrated fluid gallery 110, 122, 128, 132 or duct system for receiving electrolyte and/or process gases, particularly pressurized process gases, produced by an electrolyser 202. The assembly 204 housing block may also comprise a plurality of plates which form at least one integrated gallery. The grooved plate(s) may be formed by chemical etching. Part of a gallery may comprise a heat exchanger (figure 1, 112, 114).

Description

MANIFOLD ASSEMBLY FOR ELECTROLYSER

Description

The present disclosure relates to a manifold assembly for an electrolyser, preferably but not exclusively, an electrolyser for generating hydrogen from water. Other aspects of the present disclosure relate to an electrolysis device including the manifold assembly.

The process of using electricity to decompose water into oxygen and hydrogen gas is known as electrolysis of water. Hydrogen gas produced in this way can be used in various applications and has become widely known as an energy dense option for fuelling vehicles. In other applications, electrolysis of water may be used as a decentralised storage solution storing electrical energy as chemical energy, particularly electrical energy obtained via renewable power. In recent years, therefore, demand for hydrogen, inter alia, as a fuel for so called hydrogen fuel cells has increased rapidly.

Electrolysers can be grouped into proton exchange membrane (PEM) electrolysers, alkaline electrolysers and solid oxide electrolysers. These different types of electrolysers function in slightly different ways depending on the electrolyte material involved. Yet, some of the most prominent drawbacks of most electrolysers include overall inefficiencies and/or failure to supply hydrogen gas at pressures required for further use.

In order to maximize the amount of gas (e.g. oxygen/hydrogen) produced with common electrolysers, it is known to arrange a multitude of electrodes parallel to each other in a device known as an "electrode stack". Such electrode stacks include multiple electrolyte chambers, each between neighbouring electrodes, thereby enabling large electrode surface areas to be in contact with the electrolyte solution without requiring large space envelopes. Although electrode stacks are useful to combine a plurality of electrolysers in the smallest possible space, such known stacks are still of significant size, particularly when trying to generate hydrogen for commercial use. Using electrode stacks for domestic purposes is also not currently feasible due to its size and weight.

What is more, gases produced by "electrode stacks" are typically removed from the stack via a large and complicated system of pipes that are connected with corresponding tanks or reservoirs of the electrolysis system. For example, in hydrogen electrolysers, a first fluid line is provided between the stack and a hydrogen tank for removing hydrogen produced by the electrode stack and storing it, typically in a pressurized form, in the hydrogen reservoir. Similarly, a second fluid line is provided to remove oxygen from the stack and supply the latter to a corresponding oxygen reservoir or tank. Similarly, fluid lines are required for electrolyte supply, electrolyte drain, cooling fluids, heat exchangers, dryers, etc. The connection between the electrolysis stack and the corresponding reservoirs is not only complicated but also subject to wear and failure. Moreover, heat and pressure losses are inevitable between the stack and the corresponding functional components of the electrolysis system. Lastly, the system typically requires large storage spaces, which is particularly problematic in domestic applications, where space for technical devices is typically very limited.

It is an aim of the present disclosure to solve or at least ameliorate one or more of the problems of the prior-art.

SUMMARY OF THE INVENTION

Aspects and embodiments of the present disclosure provide a manifold assembly for electrolysers and an electrolysis device for generating hydrogen from water as claimed in the appended claims.

In one aspect, the present disclosure relates to a manifold assembly for an electrolyser, preferably an electrolyser for generating hydrogen from water, said manifold assembly comprising housing block with at least one integrated fluid gallery for receiving electrolyte and/or process gases, particularly pressurised process gases, produced by an electrolyser.

According to the present disclosure, therefore, the manifold assembly can be used to create at least one of the fluid ducts for receiving gases from a corresponding electrolyser. The manifold assembly may be directly connected to the electrode stack, as will be described in more detail below. The integrated fluid gallery may be created in various ways, including a plated design (described in more detail below) or 3D printing and will withstand high pressure. Integrated fluid ducts or fluid gallery refers to a plurality of ducts formed into an otherwise solid block, as opposed to a housing that includes individual metal pipes.

In one embodiment, the housing block comprises a plurality of plates connected to each other in a stacked manner, wherein the plates are configured to interact with each other to form the at least one integrated fluid gallery. Due to the plated construction of the manifold assembly, the latter is not only space saving but also easy to transport. In particular, the manifold assembly may either be transported in assembled form, i.e., with the plurality of plates already connected to each other or delivered as individual plates that can be stacked together on-site, e.g., bolted to a corresponding stack of electrodes in a predetermined order.

As will be described in more detail below, the plate-like structure of the manifold assembly provides various other advantages, such as integration of other functional components inside the manifold assembly, thereby further improving the compactness of the electrolyser of the present disclosure.

In another embodiment, at least one of the plurality of plates comprises one or more grooves that form part of the at least one fluid gallery. In other words, the fluid gallery may simply be constructed as grooves in one of the plates. This will reduce the costs and time spent for manufacturing the manifold assembly, because ducts can be integrated in the assembly in a quick and efficient manner.

Machining of the manifold assembly after the plates are connected is thus not required. Finally, adding the grooves to one or more of the plates before assembly will also greatly increase the accuracy with which the ducts of the one or more galleries of the manifold assembly are produced.

According to another aspect, the one or more grooves are chemically etched into the at least one plate. Chemically etching provides for a particularly clean and accurate production of the grooves and allows for highly individualized layouts of the galleries within the manifold assembly.

According to another embodiment, the manifold assembly comprises an electrical power terminal configured for connection to an electrical power supply. According to this aspect, the manifold assembly may not only be used to supply and/or receive fluids to and from the electrolysis stack, but may also act as a terminal for supplying electric power to the electrolyser. To this end, the plates may be conductive and connected to a corresponding conductor of the electrode stack.

According to another embodiment, the manifold assembly comprises a front cover plate, a rear cover plate and at least one functional plate sandwiched between the front and rear cover plates, wherein the front cover plate comprises a first gas and/or electrolyte inlet port and a second gas and/or electrolyte inlet port. As will be described in more detail below, the one or more functional plates that are sandwiched between the front and rear cover plates are configured to provide one or more functionalides to the manifold assembly. For example, as mentioned above, one type of functional plate may be provided with a plurality of grooves for providing gas ducts that connect the electrode stack with corresponding reservoirs or tanks. In some embodiments, the functional plates may even form (together or alone) a reservoir or tank for gases received from the electrode stack. Parallel functional plates, e.g., adjacent plates with grooves may be used as integral heat exchangers for transferring heat between the process fluids, such as the electrolyte and the gases of the electrolyser.

Arranging both a first gas and/or electrolyte inlet port and a second gas and/or electrolyte inlet port on the front face of the manifold assembly further simplifies connection between the manifold assembly and the electrode stack, because all of the connections between the two are preferably arranged on the same face (i.e., the front cover) of the manifold assembly. Accordingly, the manifold assembly may be directly mounted onto the electrode stack, therefore no longer requiring any external fluid pipes that run between the manifold assembly and the stack.

According to another embodiment, the manifold, particularly the front cover plate of the manifold, comprises a first gas outlet port and a second gas outlet port. In some embodiments, the first and second gas outlet ports of the manifold assembly may be provided with corresponding gas outlet valves, which the user may simply connect to corresponding appliances, such as hydrogen fuel cells or any other type of appliance that may use one or both of the process gases oxygen and/or hydrogen.

S

According to another embodiment, the at least one functional plate comprises a first fluid gallery arranged between the first gas inlet port and the first gas outlet port and a second fluid gallery arranged between the second gas inlet port and the second gas outlet port. According to this embodiment, two fluid ducts (fluid galleries) may be provided by a single functional plate, said fluid galleries being separate from each other, e.g., to separately deliver the hydrogen gas and oxygen gas to their respective tanks and/or outlet ports.

According to another embodiment, the manifold assembly comprises a first functional plate having a first plurality of grooves and a second functional plate arranged adjacent to the first functional plate and having a second plurality of grooves. The first and second plurality of grooves may extend in parallel with each other. As mentioned briefly above, arranging two functional plates adjacent to each other (i.e., stacked on top of each other), each functional plate having a plurality of grooves to provide a different fluid duct (gallery), may be used to transfer heat between the fluids contained within their respective grooves. In one example, the first functional plate with the first plurality of grooves may be connected via a gas inlet port to a process gas, such as hydrogen or oxygen provided by the electrode stack, whereas the second plurality of grooves are connected to a second inlet port, which may be an electrolyte inlet port for receiving electrolyte that is to be supplied to the electrode stack. Excess heat of the process gases received from the electrode stack may thus be transferred from the gases (e.g., hydrogen or oxygen) to the electrolyte in a simple and effective manner, before the electrolyte is supplied to the electrode stack. In other words, the manifold assembly may not only be configured to provide various fluid ducts/galleries that connect with the electrode stack but also integrate the functionality of a heat exchanger for pre-warming the electrolyte with excess heat from one or both of the process gases. Arranging the first and second plurality of grooves in a parallel manner significantly improves heat transfer between the corresponding fluids.

According to another embodiment, each of the first plurality of grooves are separated from each of the second plurality of grooves by a distance that is more than a width of the grooves. This arrangement has been found to be particularly stable and allows for sufficient transfer of heat between process fluids, where required.

According to another embodiment, the first plurality of grooves are connected to a first gas inlet port of the manifold assembly, said first gas inlet port being configured for receiving a first gas from an electrolyser, and wherein the second plurality of grooves are connected to a process fluid inlet port of the manifold assembly, said process fluid inlet port being configured to receive process fluid, such as electrolyte.

In this specification, the term "electrolyte" refers to any process fluid used by a corresponding electrolyser to generate corresponding process gases. In the example of hydrogen electrolysis, such electrolytes may be water, purified water, pure water, distilled water, solutions of electrolyte from iodized table salt, backing soda, chloride, sea salt, or lye, or any other fluid suitable for the production of hydrogen.

According to the above embodiment, the first and second grooves are used to transfer heat between a first gas (such as hydrogen) and the process fluid (the electrolyte) before the process fluid is transferred to the electrode stack.

In another embodiment, the manifold assembly comprises a third plurality of grooves connected to a second gas or electrolyte inlet port of the manifold assembly, said second gas or electrolyte inlet port being configured for receiving a second gas or electrolyte from an electrolyser. According to this embodiment, the manifold assembly may be used to receive (and in some embodiments process) all of the fluids of the electrolysis system, namely the electrolyte and their corresponding gases produced by the electrode stack. In some embodiments, the manifold assembly may further be provided with return fluid inlet ports, which may be connected to the electrode stack to return electrolyte that is drained from the stack, e.g., after it has passed through an electrolyser cell without being separated into gases.

In another embodiment, the manifold comprises a fourth plurality of grooves connected to a cooling fluid inlet port of the manifold assembly, said cooling fluid inlet port being configured for receiving fluid from an external cooling fluid circuit. According to this embodiment, the manifold assembly cannot only be provided to transfer heat between the process fluids but can actively remove heat from the system via a cooling circuit. Alternatively or additionally, the cooling fluid circuit may also be used to preheat the electrolyte during a start-up phase, i.e., when heat of the process gases is not yet available.

In another embodiment, each of the plates has a thickness below 5 mm.

Thicknesses below 5 mm provide for a particularly space saving manifold assembly and, at the same time, facilitate heat transfer between the process fluids received by the manifold assembly.

In another embodiment, the plates are made of any one of stainless steel, aluminium, titanium, or alloys thereof. The metal materials used to form the plates of the manifold assembly facilitate heat transfer and the possibility of introducing electrical power into the electrode stack via the manifold assembly.

In another embodiment, plates are permanently connected to each other, preferably by means of fusion bonding. Permanently connecting the plates to each other is particularly advantageous when handling pressurized process fluids. In some preferred embodiments of the present disclosure, the electrolysis device utilizes pressurized electrolyte in a flow-through electrolysis process. As a consequence of the use of pressurized electrolyte, the process gases may also be pressurized, which is particularly useful, since at least hydrogen is typically required to be stored under pressure. Due to the diffusion bonded plates, pressurized fluids may be securely contained within the fluid ducts or galleries of the manifold assembly.

In another embodiment, the manifold assembly comprises a gas outlet port for discharging a gas produced by the electrolyser, wherein the gas outlet port comprises one or more connectors for mounting an expander-generator to the gas outlet port, such that pressurised first gas discharged via the gas outlet port may be used to drive, particularly rotate, the expander-generator. In the example of a hydrogen electrolyser, the gas outlet port may be connected to a fluid gallery or fluid line within the manifold assembly that is configured to receive oxygen gas from the electrode stack. As mentioned above, the oxygen gas may be pressurized due to the use of pressurized electrolyte during the electrolysis process. The energy stored within the pressurized oxygen may partly be recovered by means of an expander-generator that is connected or connectable to the gas outlet port of the manifold assembly. The manifold assembly is thus part of a modular system, which may be extended with an expander-generator to recycle some of the energy stored within the process fluids.

In another embodiment, the manifold assembly comprises an electrolyte inlet port for receiving process fluid, said electrolyte inlet port comprising one or more connectors for mounting an electrolyte supply pump to the electrolyte inlet port. Again, the manifold assembly may be part of a modular system, in which an electrolyte supply pump may be directly mounted onto any surface of the manifold assembly.

According to another aspect of the present disclosure, there is provided an electrolysis system for generating hydrogen from water, said electrolysis system comprising a manifold assembly as described above and an electrolyser comprising one or more electrodes for producing pressurised gas, wherein the electrolyser is configured to supply said pressurised gas to the at least one fluid gallery of the manifold assembly.

In one embodiment, the electrolyser comprises a stack of electrodes sandwiched between a front cover and a stack rear cover, wherein the manifold assembly acts as the front cover of the electrolyser. In other words, the electrodes of the electrolyser may be directly stacked onto the manifold assembly, thereby further reducing the space requirement of the electrolysis device and further integrating the electrolyser into the manifold assembly. In some embodiments, the electrolyser may comprise two manifold assemblies, one of which acts as the front cover and the other as the rear cover of the electrode stack.

According to another embodiment, the electrolysis device comprises at least one fastening device, preferably a plurality of fastening bolts, extending through the stack of electrodes and the manifold assembly, and wherein the at least one fastening device is configured to secure the stack of electrodes to each other and to the manifold assembly. It follows that a single fastening device may be used for two purposes: firstly, the fastening device may be used to connect the electrode stack with the manifold assembly; secondly, the fastening device may be used to secure the electrodes of the stack to each other.

In another embodiment, the electrolyser comprises a first gas collection duct connected to first gas inlet port of the manifold assembly and/or an electrolyte supply duct connected to an electrolyte outlet port of the manifold assembly, and/or a second gas collection duct connected to a second gas inlet port of the manifold assembly. In other words, gases produced by the electrolyser may be transferred to the manifold directly via first and/or second gas collection ducts.

Similarly, electrolyte may be supplied via the manifold assembly into an electrode supply duct of the electrolyser.

In another embodiment, the manifold assembly and the electrolyser are electrically connected to each other, such that an electric current may flow between the manifold assembly and the electrolyser. As set out above, one option of creating an electric connection between the manifold assembly and the electrolyser is to manufacture some or all of the parts of the manifold assembly and the electrolyser of an electrically conductive material such that electric current may flow between one end of the manifold assembly and an opposite end of the electrolyser stack.

According to another embodiment, the manifold assembly comprises a negative high voltage DC terminal, and wherein the electrolyser comprises a positive high voltage DC terminal arranged at an opposite end to the manifold assembly.

In another embodiment, the manifold assembly and/or the electrolyser comprise electrically insulated cables and/or an electrically insulated outer surface. The electrical insulation protects users from electrical shock by an electric current flowing between the manifold assembly and the electrolyser during the electrolysis process.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, and the claims and/or the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and all features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

The aforementioned and other features and advantages of this disclosure, and the manner of attaining them, will become more apparent and the disclosure will be better understood by reference to the following description of embodiments of the disclosure taken in conjunction with the accompanying drawings, wherein: FIG. 1 shows a schematic hydraulic diagram of an electrolysis device according to an embodiment of the present disclosure including an embodiment of a manifold assembly according to the present

disclosure;

FIG. 2 shows a schematic perspective view of an electrolysis device according

to an embodiment of the present disclosure;

FIG. 3 shows a schematic perspective view of another embodiment of the electrolysis device according to the present disclosure; FIG. 4 shows a schematic cross-sectional view of a manifold assembly according to an embodiment of the present invention; shows an enlarged view of the circled part in FIG. 4; shows a schematic cross-sectional view of the manifold assembly shown schematically in FIG. 4; shows an enlarged view of the circled part of FIG. 6; shows a schematic cross-sectional view of the embodiment of the FIG. 5 FIG. 6 FIG. 7 FIG. 8 manifold assembly shown in FIGs. 4 to 7; FIG. 9 shows an enlarged view of the circled part of the manifold assembly of FIG. 8.

FIG. 1 shows a schematic hydraulic diagram of an electrolysis device 100 according to an embodiment of the present disclosure. The electrolysis device comprises an electrolyser 102, which may be provided in the form of an electrode stack that will be explained in more detail below. The electrolyser 102 is only schematically represented as a black box in FIG. 1. It should be understood that the electrolyser could be any electrolyser that is configured to split an electrolyte into process gases. In this embodiment, the electrolyser is a hydrogen electrolyser for generating hydrogen from aqueous electrolyte solutions. The electrolyser may be any type of membrane or membraneless electrolyser. In one particularly preferred embodiment, the electrolyser may be a flow-through electrolyser, in which the electrolyte is forced through a number of porous electrodes during the electrolysis process. As the electrolyte moves through the porous electrodes, it is separated into process gases depending on the polarity of the electrode. In a particular example of the electrolyser 102 for hydrogen production, the electrolyte may be pressurized, such that a pressure drop occurs between opposing surfaces of the flow-through electrodes. On a negative electrode (cathode-electrode), hydrogen is produced as the electrolyte passes through the porous electrode. On the positive electrode (anode-electrode) oxygen is produced when the electrolyte passes through the porous electrode.

As is also derivable from FIG. 1, the electrolyser 102 is connected to a plurality of fluid ducts or galleries, tanks, heat exchangers and other functional parts that are required for the electrolysis process. In particular, the electrolyser 102 comprises an electrolyte inlet port 106 that is connected to an electrolyte supply pump 108 via an electrolyte supply gallery 110. As will be described in more detail below, the fluid ducts of the electrolyte supply gallery 110 may include one or more heat exchangers 112, 114 for preheating the electrolyte before it is supplied to the electrolyser.

At an inlet end, the electrolyte pump 108 is connected to an electrolyte inlet valve 116, which may be used to selectively provide the system with fresh electrolyte.

The electrolyser 102 comprises a first gas outlet 118 that is connected to a first gas tank, i.e., a hydrogen gas tank 120 via a second fluid gallery 122 schematically shown in FIG. 1. The second fluid gallery 122 is a system of ducts that connects the first gas outlet 118 of the electrolyser to the first gas tank 120 and may thus be considered as a first gas inlet gallery. Parts of the second fluid gallery 122 may form part of a first heat exchanger 112. As indicated above, another part of the heat exchanger 112 may be provided by the first fluid gallery, i.e., the electrolyte supply gallery 110. Accordingly, the first heat exchanger may be used to transfer heat from the hydrogen gas within the second fluid gallery 122 to the electrolyte that is supplied to the electrolyser via the first fluid gallery, or electrolyte supply gallery 110.

The electrolyser comprises a second process gas outlet 124, which is connected to a second gas reservoir, i.e., an oxygen tank 126 via a third fluid gallery 128. The third fluid gallery 128 is a system of fluid ducts that connects the second gas outlet 124 of the electrolyser to the oxygen tank 126. As such, the third fluid gallery 128 may be considered as a second gas inlet gallery. A part of the third fluid gallery 128 may be part of a second heat exchanger 114, which may also be used to preheat the electrolyte supplied to the electrolyser. Accordingly, another part of the second heat exchanger 114 may be part of the first fluid gallery, i.e., the electrolyte supply gallery, 110. Excess heat of the pressurized oxygen gas provided by the electrolyser via the second gas outlet 124 may be transferred to the electrolyte before it is supplied to the electrolyte inlet 106 of the electrolyser 102.

As mentioned above, electrolyte that penetrates the porous structure of the flow-through electrodes of the electrolyser 102 may be partly split into either hydrogen or oxygen. However, typically there will also be a portion of the electrolyte that remains in its original form, i.e., is not split into gases and is thus available to be re-used. In order to re-use the electrolyte not turned into gases, the electrolyser 102 comprises at least one electrolyte outlet port 130, which is connected to a fourth gallery, i.e., an electrolyte drain gallery, 132. The drain gallery 132 may connect the electrolyte outlet port 130 of the electrolyser 102 to an inlet end of the electrolyte supply pump 108. Accordingly, electrolyte that is not used within the electrolyser 102 may be recycled and re-supplied to the inlet port 106 of the electrolyser 102 via the electrolyte supply pump 108 and the corresponding first gallery 110.

The hydrogen and oxygen tanks 120, 126 are configured to hold pressurized hydrogen and oxygen until it is utilized for their intended purpose. In terms of the hydrogen, this may be used as an energy source for hydrogen fuel cells or directly combusted in hydrogen engines, for example when driving heavy machinery, such as agricultural plants. The oxygen stored in the oxygen tank 126, on the other hand, may be used in cleaning sewage.

Both the hydrogen tank 120 and the oxygen tank 126 include a gas outlet port, which may be connected to further functional structures, such as dryers 134, 136. The dryers 134 and 136, which are arranged downstream of the hydrogen tank 120 and the oxygen tank 126 respectively are configured to dehumidify the oxygen and hydrogen stored within the tanks 120, 126. In some embodiments, the dryers 134, 136 may be constructed as further fluid galleries, e.g., a system of ducts that are connected to form part of another heat exchanger to cool down the process gases and, therefore, reduce the humidity levels, for example by means of condensation within the fluid galleries of the dryers. Any moisture removed from the gases within the dryers 134, 136 may drain back into the tanks 120, 126. Both the hydrogen tank 120 and the oxygen tank 126 are provided with drain ports that are connected to the drain gallery 132 discussed above. Accordingly, the moisture removed from the process gases via the dryers 134, 136 may ultimately be recycled and supplied to the inlet end of the electrolyte supply pump 108 once again.

Downstream of the dryers 134, 136, the electrolysis device 100 may be provided with a first gas outlet valve 138 that acts as a first gas outlet port of the system and a second gas outlet valve 140 that acts as an oxygen outlet port of the system. The oxygen outlet port provided with the second gas outlet valve 140 may be connected to an expander-generator 142 that may be used to recycle some of the energy set free when expanding the oxygen gas stored within the oxygen tank 126.

FIG. 1 schematically shows a manifold assembly 104 according to an embodiment of the present disclosure in dashed lines. According to the present disclosure, the manifold assembly 104 is a compact arrangement and may be directly mounted onto the electrolyser 102 and comprises a number of the functional parts of the electrolysis device 100 described above. In particular, the manifold assembly 104 may integrate the first, second, third and fourth fluid galleries 110, 122, 128, 132 as well as the hydrogen tank 120, the oxygen tank 126, the two heat exchangers 112, 114 and the dryers 134, 136. The manifold assembly 104 is an integral block that may simply be connected to the functional components (such as pumps, electrolyser, etc.) shown outside of the dashed lines by the user.

In particular, an electrolyte inlet port 144 of the manifold assembly may be connected to an outlet end of the electrolyte supply pump 108. An electrolyte outlet port 146 of the manifold assembly 104 may be connected to the inlet side of the electrolyte supply pump. The electrolyte inlet port 144 defines a first end of the electrolyte supply gallery 110. The electrolyte outlet port 146 defines a second end of the electrolyte drain gallery 132. The first gas outlet port 118 of the electrolyser 102 may be connected to a first gas inlet port of the manifold assembly 104. Similarly, the second gas outlet 124 of the electrolyser may be directly connected to a corresponding second gas inlet port of the manifold assembly 104. The first gas inlet port of the manifold assembly 104 defines a first end of the second fluid gallery 122. The second gas inlet port of the manifold assembly 104 defines a first end of the third fluid gallery 128. A drain inlet port of the manifold assembly 104 may be directly connected to the electrolyte drain port 130 of the electrolyser and define a first end of the drain gallery 132. A first gas outlet port of the manifold assembly 104 may be connected to the first gas valve 138. A second gas outlet port of the manifold assembly 104 may be connected to the second gas outlet valve 140.

During the electrolysis process, the electrolyser is provided with electrical power, in order to split the electrolyte into process gases, such as hydrogen and oxygen.

In the embodiment of Fig. 1, the manifold assembly 104 comprises an electrical terminal 150, for connecting one polarity of the electrical power supply (not shown) to the electrolysis device 100 via the manifold assembly 104. In Figure 1 the terminal 150 is connected to a negative polarity but it is also feasible to connect a positive polarity to the system via the terminal 150.

A schematic perspective view of another embodiment of the electrolysis device according to the present disclosure is shown in FIG. 2. The electrolysis device of FIG. 2 shows an electrolyser 202 in the form of an electrode stack. In other words, the electrolyser 202 comprises a plurality of plate-like electrodes stacked adjacent to each other. In the example of FIG. 2, the plate-like electrodes 206, 208, 210 are cylindrical electrodes stacked on top of each other. However, it will be appreciated that any shape may be used to form the stacked electrolyser 202.

At a first end 201 of the electrode stack 202, the electrode stack 202 is connected to a manifold assembly 204. The manifold assembly 204, which will be described in more detail below, may act as a front cover of the electrode stack 202. At an opposite, second end 203 of the stacked electrolyser 202, a rear cover 212 is provided. The rear cover 212 comprises a plurality of openings 214 that extend through the stack and, preferably, also through the manifold assembly.

The openings 214, therefore, provide a guide channel for fastening elements, such as fastening bolts that extend through the front cover, the electrodes of the stack, and the manifold assembly. The fastening elements may thus secure the plate-like electrodes 206, 208, 210 to each other and, at their respective ends of the stack, to the manifold assembly 204 and the rear cover 212 respectively. The rear cover 212 of the electrolyser 202 also comprises an electrical terminal 214 for connecting one end of an electrical power source to the electrolysis device 200. In some embodiments, the electrical terminal 214 may be a positive terminal. Similarly, a negative terminal may be provided on the manifold assembly 204, similar to what has been described with reference to FIG. 1.

Although this is not specifically shown in FIG. 2, the manifold assembly 204 comprises a plurality of ports that provide a fluid connection between the electrolyser 202 and the manifold assembly 204. In particular, the manifold assembly 204 may include an electrolyte supply/outlet port, two process gas inlet ports and an electrolyte drain port, all of which are arranged on a front face 216 of the manifold assembly 204, particularly at the interface with the stacked electrode electrolyser 202. Of course, it will be appreciated that the electrolyte supply port, the two process gas inlet ports, and the electrolyte drain port may be arranged on any surface of the manifold assembly 204, although it may be advantageous to arranged all of the ports on a common surface for ease of connection with other components in the system.

The exchange of fluids between the manifold assembly 204 and the electrolyser 202 is schematically shown by arrows 218, 220. A first arrow 218 schematically shows the flow direction of electrolyte from the manifold assembly 204 into the electrolyser 202. To this end, the electrolyser 202 may include one or more electrolyte supply ducts that transport electrolyte from the electrolyte supply port/ports of the manifold assembly 204 into gaps between the electrodes 206, 208, 210 of the electrolyser. Hydrogen and oxygen gases produced during electrolysis will, in turn, be transported back towards the manifold assembly in an opposite, second direction indicated by the second arrow 220 in FIG. 2. To this end, the electrolyser may include at least one hydrogen collection channel and at least one oxygen collection channel, which are separate from each other and both connected to a separate process gas inlet port (not shown) of the manifold assembly 204.

The electrolyser 202 may further include an electrolyte drain channel, which is used to revert electrolyte that has penetrated the flow-through electrodes but has not been separated into the respective process gases, back to the manifold assembly. To this end, the drain channel of the electrolyser 202 is connected with a drain inlet port (not shown) of the manifold assembly 204.

The manifold assembly 204 comprises a variety of additional inlet and outlet ports on its front face 216. In particular, the manifold assembly 204 shown in FIG. 2 comprises an electrolyte inlet port 222 that may be provided with connectors (not shown) for directly mounting an electrolyte supply pump (not shown) to the electrolyte inlet port 222 of the manifold assembly 204. An electrolyte outlet port 223 for drained/recycled electrolyte is also arranged on the front face of 216 of the manifold assembly 204 and may be connected to an inlet end of the electrolyte supply pump. A similar electrolyte supply pump is shown as item 108 in FIG. 1.

The front face 216 of the manifold assembly 204 further includes first and second process gas outlets 224, 226. The first process gas outlet 224 may be a hydrogen gas outlet port, whereas the second process gas outlet port may be an oxygen gas outlet port. The first and second process gas outlet ports 224, 226 may be used by the operator to attach fluid lines for connecting the electrolysis device to a consumer of the process gas, such as a hydrogen fuel cell. Although not specifically shown in FIG. 2, the manifold assembly 204 may also be provided with a drain port for reverting drained electrolyte back to the electrolyte supply pump mounted onto the electrolyte inlet port 222 of the manifold assembly.

As is schematically shown in FIG. 2 by the dashed lines of the manifold assembly 204, the manifold assembly 204 comprises a plurality of plates 230, 232, 234, 236, 238 connected to each other in a stacked manner, similar to the stacked electrodes 206, 208, 210 of the electrolyser 202. Together, the plates 230, 232, 234, 236, 238 of the manifold assembly 204 define a pressure tight fluid system for connection with the electrolyser 202 that includes some or all of the functional components described with reference to FIG. 1. In particular, the plates of the manifold assembly 204 interact with each other to form at least one fluid gallery for receiving electrolyte and/or process gases, particularly pressurized process gases, from the electrolyser 202. To this end, in the embodiments shown, at least one of the plates 230 to 238 of the manifold assembly 204 is provided with one or more grooves that form part of the at least one fluid gallery, as will be described in more detail with respect to FIGs. 4 to 9.

The individual plates of the manifold assembly may be permanently connected to each other, preferably by fusion bonding. However, it is alternatively also feasible to connect the plates to each other by any other means that facilitates pressure tightness for receiving the pressurized process gases from the electrolyser 202.

The plates are made of any one of stainless steel, aluminium, titanium, or alloys thereof. Accordingly, the plates of the embodiment in FIG. 2 are electrically conductive, such that a current may flow between the plates 230 to 238 of the manifold assembly 204 and the rear face/rear cover 212 of the electrolyser 202. The plates of the manifold assembly 204 may thus be covered by a housing structure made of an insulating material so as to prevent the operator from electric shocks.

FIG. 3 shows an alternative embodiment of an electrolysis device according to the present disclosure. Similar to the embodiment of FIG. 2, the electrolysis device 300 of FIG. 3 comprises an electrolyser 302 that comprises a stack of parallel plate-like electrodes 306, 308, 310.

In contrast to the first embodiment shown in FIG. 2, however, the electrolysis device 300 of the second embodiment shown in FIG. 3 comprises two manifold assemblies 304, 306. A first manifold assembly 304 is connected to a first end of the electrode stack, whereas a second manifold assembly 306 is connected to an opposite, second end of the electrode stack. According to this embodiment, the two manifold assemblies 304, 306 may act as front and rear covers of the electrode stack of the electrolyser 302. Both manifold assemblies 304, 306 comprise a plurality of plates that define at least one fluid gallery, similar to what has been described with reference to the manifold assembly 104 of Fig. 2.

The electrolysis device 300 comprises a plurality of fastening elements 312 extending through the two manifold assemblies 304, 306 and the electrolyser 302. The fastening elements not only connect the plate-like electrodes 306, 308, 310 of the electrolyser 302 with each other but also connect the manifold assemblies 304, 306 with the front and rear end of the electrolyser 302. As will be appreciated, there may be gaskets between each of the electrodes 306, 308, 310 of the electrolyser to prevent process fluids from leaking out of the electrolyser between the electrodes. Similarly, gaskets may be provided at the interfaces between the manifold assemblies 304, 306 and the electrolyser 302 to seal the inlet and outlet ports.

In the embodiment on FIG. 3, both manifold assemblies 304 and 306 comprise a plurality of plates that define at least one fluid gallery within the manifold assembly. However, in contrast to the single manifold assembly of the example shown in FIG. 2, the first manifold assembly 304 that is configured to be arranged at a top end of the electrolyser, when in use, may be considered as a gas manifold assembly, which is configured to receive the process gases from the electrolyser. In other words, the first manifold assembly 304 may include at least two fluid galleries, one for the hydrogen gas and one for the oxygen gas produced by the electrolyser 302. Similar to FIG. 1, the first manifold assembly 304 may then also include one or more gas tanks, such as an oxygen tank and a hydrogen tank for (temporarily) storing the oxygen and hydrogen produced by the electrolyser 302.

The second manifold assembly 306 is arranged so as to be on the bottom of the electrolyser 302, when using the electrolysis device 300 in a vertical setup. The second manifold assembly 306 may be considered as an electrolyte storage manifold assembly. The second manifold assembly 306 may thus be provided with at least two fluid galleries, one electrolyte supply gallery and one electrolyte drain gallery. The electrolyte supply pump may thus be connectable directly to the second manifold assembly 306 in order to supply electrolyte to the second manifold assembly and, ultimately, to the electrolyser 302. Electrolyte that penetrates the flow-through electrodes 306, 308, 310 of the electrolyser 302 without being split into oxygen and hydrogen, may be drained via the drain channels of the electrolyser 302 into the drain gallery of the second manifold assembly 306, assisted by gravity.

With such a vertical electrolysis device 300 shown in FIG. 3, it may no longer be necessary to provide drain ports on the oxygen and hydrogen tanks, contrary to what has been shown with respect to FIG. 1.

FIG. 3 further shows that the electrolysis device 300 comprises a first electrical terminal 314 and a second electrical terminal 316 arranged at opposite ends of the electrolyser. In particular, the first electrical terminal 314 is connected at the gas manifold assembly end of the electrolyser, i.e., on the end of the first manifold assembly 304. The second electrical terminal is connected to the opposite end of the electrolyser, i.e., at the electrolyte storage manifold assembly end. The first electrical terminal 314 is preferably a negative terminal, whereas the second terminal 316 is preferably a positive terminal, such that hydrogen is produced towards the top end of the electrolyser 302.

The first and second manifold assemblies 304, 306 of the second embodiment shown in FIG. 3 comprise multiple plates that define the fluid ducts/fluid galleries described above. These plates are arranged within a housing structure of the manifold assemblies that is electrically insulating to protect the operator.

Compared to the first embodiment of FIG. 2, the electrolysis device 300 of FIG. 3 requires lower manufacturing costs and further reduces the required space envelope. Although this is not specifically shown in FIG. 3, the process gas outlet ports and the electrolyte inlet/outlet ports of the manifold assemblies may be arranged at any external surface of the manifold assemblies, whether these are front, rear or side faces of the manifold assemblies 304, 306.

Referring to FIGs. 4 to 9, there are shown schematic cross-sections of a manifold assembly according to the first embodiment shown in FIG. 2.

With particular reference to FIG. 4, there is shown a cross-section parallel to the rear face of the manifold assembly shown in FIG. 2. The cross-section shows a functional plate that is provided with a plurality of grooves that are schematically represented as a blue area and shown in more detail in FIG. 5. The grooves may be chemically etched into the functional plate shown in the cross-section in FIG. 4 so as to form part of a fluid gallery. As an example, the fluid gallery shown in the cross-section of FIG. 4 may be a cooling fluid gallery 406, which is connected to a cooling fluid inlet and outlet port (not shown) of the manifold assembly. It follows that cooling fluid may be introduced into the manifold assembly via said ports and distributed along the fluid gallery defined by the grooves of the functional plate shown in FIG. 4.

The functional plate shown in FIG. 4 further includes a first opening 408 and a second opening 410, which form part of two separate process gas storage tanks, such as the oxygen and hydrogen tanks described above. Together with corresponding openings of adjacent plates of the manifold assembly, two separate hollow chambers (the tanks) are created within the manifold assembly by aligning the corresponding openings of adjacent plates.

The cooling fluid gallery 406 shown schematically in FIG. 4 may be arranged to surround the first and second openings and thus surround the oxygen and hydrogen gas tanks of the manifold assembly. Accordingly, the cooling system may be used to transfer heat from the process gases stored within the tanks into the cooling fluid running through the grooves that define the cooling fluid gallery 406.

FIG. 4 further shows an interface region 412, which corresponds to a part of the manifold assembly that is later connected to the electrolyser (not shown). The interface area 412 comprises a plurality of fastening openings 414 for receiving fastening elements described with reference to the embodiment in FIG. 3, for example.

Turning to FIG. 5, there is shown an enlarged view of the grooves of the functional plate shown in the cross-section of FIG. 4 that define the cooling fluid gallery 406. The functional plate 405 includes a plurality of grooves 416, 418, 420 that may be chemically etched into the surface of the plate. The depth of the grooves is lower than the thickness of the plates. However, in alternative embodiments, the grooves are replaced by slots that extend through the entire thickness of the plate and define the fluid gallery together with adjacent (non-slotted) plates. In some embodiments, holes or slots may be introduced by means of a Laser during the manufacturing process.

The plurality of grooves 416, 418, 420 of the cooling fluid gallery shown in FIG. 4 may extend in a substantially rectangular fashion around the perimeter of the first and second openings 408, 410 shown in FIG. 4. In some embodiment, the cooling fluid inlet and outlet ports are connected with the grooves 416, 418, 420 in such a way that the cooling fluid is introduced into the grooves that are closest to the process gas storage tanks, whereas a cooling fluid outlet port is connected to the outermost grooves, so as to remove as much heat from the process gases stored within the tanks as possible.

FIG. 6 shows a schematic cross-section through a second plane of the manifold assembly shown in FIG. 2. The cross-section in FIG. 6 shows a second plate that is arranged in parallel with the first plate shown in FIG. 4. Similar to the first plate, the second plate also comprises a plurality of grooves that define various fluid galleries. In particular, a first plurality of grooves defines a hydrogen gas inlet gallery 506. A second plurality of grooves defines an oxygen gas inlet gallery 508. A third plurality of grooves defines a hydrogen outlet gallery 510, whereas a fourth plurality of grooves defines an oxygen outlet gallery 512. Similar to what has been described with reference to FIG. 1, the hydrogen inlet gallery 506 connects a first gas inlet port of the manifold assembly 204 with a first gas tank, i.e., the oxygen tank 514, which is created by the plurality of (rectangular) openings in adjacent plates discussed above. The oxygen gas inlet gallery 508 connects a second process gas inlet port of the manifold assembly 204 with the oxygen tank 516. Similarly, the hydrogen outlet gallery 510 connects the hydrogen tank 514 with a first (hydrogen) outlet port (not shown) of the manifold assembly. The oxygen outlet manifold connects the oxygen tank 516 with a second (oxygen) gas outlet port (not shown) of the manifold assembly 204.

As will be appreciated, in the embodiment shown in FIG. 6, a single plate of the manifold assembly may be used to form the fluid galleries for both process gases of the electrolysis device. Accordingly, the manifold assembly of the present disclosure is particularly compact and may be manufactured at low cost.

The functional plate of FIGs. 6 comprises an interface region 520 with a plurality of fastening openings 518. The fastening openings 518 align with the fastening openings 414 of the interface area 412 of the plate 405 shown in FIG. 4.

FIG. 7 shows an enlarged view of some of the grooves of the hydrogen gas outlet gallery 510 shown in FIG. 6. Similar to the grooves of the cooling fluid gallery shown in FIG. 5, the grooves 522, 524, 526 are arranged in parallel and allow for the hydrogen gas to be directed over a large surface area of the plate 528 shown in FIG. 6.

Although FIGs. 4 and 6 only show single plates that may define the cooling fluid galleries and the process gas galleries, it should be understood that a large number of parallel plates may be used to define the cooling fluid galleries and the process gas galleries. In one specific example, plates defining cooling fluid galleries, such as the plate shown in FIG. 4, are alternatingly interspersed between plates that define the process gas galleries shown in FIG. 6, and possibly further plates with grooves that define electrolyte galleries.

The above arrangement of alternating fluid galleries on adjacent plates of the manifold assembly 204 is schematically represented in the side section of FIGs. 8 and 9. The cross-section in FIG. 8 shows an electrolyte inlet port 602 and electrolyte outlet port 604, which may be used to introduce and remove electrolyte to and from the manifold assembly 204. The oxygen gas tank 516 is also derivable from FIG. 8.

An enlarged view of the cross-section shown in FIG. 8 that shows the fluid ducts of the manifold assembly 204 in more detail is shown in FIG. 9. As shown, a plurality of plates 702, 704 that define process gas galleries, such as the plate shown in FIG. 6 are interspersed between plates 706, 708 that define a cooling fluid gallery. The grooves 710, 712 of the plate 702, 704 extend in a vertical direction in FIG. 9, whereas the grooves or ducts 714, 716 of the plates 706, 708 extend into the drawing plane of FIG. 9. Accordingly, the fluid ducts (e.g., grooves) of the adjacent plates of the manifold assembly extend perpendicularly with respect to each other. Excess heat stored within the process gases that are guided through the process gas galleries defined by the ducts 710, 712 may be transferred to the cooling fluid that is provided within the ducts 714, 716 of the cooling fluid gallery. Accordingly, the fluid galleries within the manifold assembly that are closely arranged on adjacent plates can act as integrated heat exchangers that are part of the manifold assembly.

Of course, the present disclosure is not limited to the particular type or layout of the fluid galleries shown in the examples of FIGs. 4 to 9. In particular, it will be understood that, in some embodiments, other fluid galleries may also be provided on some or all of the plates of the manifold assembly, such as electrolyte supply galleries and electrolyte drain galleries discussed with reference to FIG. 1, for example. In some examples, plates that define the electrolyte supply gallery may be interspersed between plates that define the process gas inlet galleries to transfer heat from the process gases to the electrolyte before the electrolyte is supplied to the electrolyser via the interface portion discussed above.

The present disclosure is not limited to the specific embodiments described with reference to FIGs. 1 to 9. Rather, the disclosure also includes any combination of features disclosed therein.

Claims

Claims 1. 2. 3. 4. 5. 6.A manifold assembly for an electrolyser, preferably electrolyser for generating hydrogen from water, said manifold assembly comprising a housing block with at least one integrated fluid gallery for receiving electrolyte and/or process gases, particularly pressurised process gases, produced by an electrolyser.
The manifold assembly according to Claim 1, wherein the housing block comprises a plurality of plates connected to each other in a stacked manner, wherein the plates are configured to interact with each other to form the at least one integrated fluid gallery.
The manifold assembly according to Claim 2, wherein at least one of the plurality of plates comprises one or more grooves that form part of the at least one fluid gallery.
The manifold assembly according to Claim 3, wherein the one or more grooves are chemically etched into the at least one plate.
The manifold assembly according to any one of Claims 1 to 4, comprising an electrical power terminal configured for connection to an electrical power supply.
The manifold assembly according to any one of Claims 1 to 5, comprising a front cover plate, a rear cover plate and at least one functional plate sandwiched between the front and rear cover plates, wherein the front cover plate comprises a first gas and/or electrolyte inlet port and a second gas and/or electrolyte inlet port.
7. The manifold assembly according to Claim 6, wherein the manifold, particularly the front cover plate of the manifold, comprises a first gas outlet port and a second gas outlet port.
8. The manifold assembly according to Claim 7, wherein the at least one functional plate comprise a first fluid gallery arranged between the first gas inlet port and the first gas outlet port and a second fluid gallery arranged between the second gas inlet port and the second gas outlet port.
9. The manifold assembly according to any one of Claims 1 to 8, wherein the manifold assembly comprises a first functional plate having a first plurality of grooves and a second functional plate arranged adjacent to the first functional plate and having a second plurality of grooves, wherein the first and second plurality of grooves preferably extend perpendicularly to each other.
10. The manifold assembly according to Claim 9, wherein each of the first plurality of grooves are separated from each of the second plurality of grooves by a distance that is more than a width of the grooves.
11. The manifold assembly according to Claim 9 or 10, wherein the first plurality of grooves are connected to a first gas inlet port of the manifold assembly, said first gas inlet port being configured for receiving a first gas from an electrolyser, and wherein the second plurality of grooves are connected to a process fluid inlet port of the manifold assembly, said process fluid inlet port being configured to receive process fluid, such as electrolyte.
12. The manifold assembly according to any one of Claims 9 to 11, wherein the manifold assembly comprises a third plurality of grooves connected to a second gas or electrolyte inlet port of the manifold assembly, said second 13. 14. 15. 16. 17. 18.gas or electrolyte inlet port being configured for receiving a second gas gas or electrolyte from an electrolyser.
The manifold assembly according to any one of Claims 9 to 12, wherein the manifold comprises a fourth plurality of grooves connected to a cooling fluid inlet port of the manifold assembly, said cooling fluid inlet port being configured for receiving fluid from an external cooling fluid circuit.
The manifold assembly according to any one of Claims 2 to 13, wherein each of the plates has a thickness below 5mm.
The manifold assembly according to any one of Claims 1 to 14, wherein the plates are made of any one of stainless steel, aluminium, titanium, or alloys thereof.
The manifold assembly according to any one of Claims 2 to 15, wherein the plates are permanently connected to each other, preferably by means of fusion bonding.
The manifold assembly according to any one of Claims 1 to 16, wherein the manifold assembly comprises a gas outlet port for discharging a gas produced by the electrolyser, wherein the gas outlet port comprises one or more connectors for mounting an expander-generator to the gas outlet port, such that pressurised first gas discharged via the gas outlet port may be used to drive, particularly rotate, the expander-generator.
The manifold assembly according to any one of Claims 1 to 17, wherein the manifold assembly comprises an electrolyte inlet port for receiving electrolyte, said electrolyte inlet port comprising one or more connectors for mounting an electrolyte supply pump to the electrolyte inlet port.
19. The manifold assembly according to any one of Claims 1 to 18, wherein the plurality of plates together define at least one tank inside the manifold assembly for the storage of a process gas, particularly a pressurised process gas.
20. An electrolysis device for generating hydrogen from water, said electrolyser assembly comprising at least one manifold assembly according to any one of Claims 1 to 19 and an electrolyser comprising one or more electrodes for producing pressurised gas, and wherein the electrolyser is configured to supply said pressurised gas to a first gas inlet port of the manifold assembly.
21. The electrolysis device of Claim 20, wherein the electrolyser comprises a stack of electrodes sandwiched between a front cover and a stack rear cover, wherein the manifold assembly acts as the front cover of the electrolyser.
22. The electrolysis device of Claim 21, wherein the electrolysis device comprises at least one fastening device, preferably a plurality of fastening bolts, extending through the stack of electrodes and the manifold assembly, and wherein the at least one fastening device is configured to secure the stack of electrodes to each other and to the manifold assembly.
23. The electrolysis device of any one of Claims 20 to 22, wherein the electrolyser comprises a first gas collection duct connected to first gas inlet port of the manifold assembly and/or an electrolyte supply duct connected to an electrolyte outlet port of the manifold assembly, and/or a second gas collection duct connected to a second gas inlet port of the manifold assembly.
24. The electrolysis device of any one of Claims 20 to 23, wherein the manifold assembly and the electrolyser are electrically connected to each other, such that an electric current may flow between the manifold assembly and the electrolyser.
25. The electrolysis device of Claim 24, wherein the manifold assembly comprises a negative high voltage DC terminal, and wherein the electrolyser comprises a positive high voltage DC terminal arranged at an opposite end to the manifold assembly.
26. The electrolysis device of Claim 24 or 25, wherein the manifold assembly and/or the electrolyser comprise electrically insulated cables and/or an electrically insulated outer surface.