Method for measuring current in electrolytic cell stack and electrolytic cell

Abstract

A method for measuring current in an electrolyzer cell stack is provided, comprising the steps of providing at least one sensor (11) having an element responsive to the presence of magnetic flux and / or magnetic flux changes adjacent an input or outlet manifold channel (6, 7) outside a current injector plate of the electrolyzer stack, ensuring an electrical or wireless connection between the sensor (11) and a recording and / or display device, providing a potential difference between two current injector plates with the electrolyzer cell stack disposed therebetween, capturing a signal value indicative of the magnetic flux and / or magnetic flux changes at the sensor location by the at least one sensor (11), and making the at least one signal value available for storage and / or transmission to a remote location via a wired and / or wireless connection.

Description

[Technical field]

[0001] The present invention relates to a method for measuring current in an electrolyser stack and to an electrolyser. [Background technology]

[0002] US Patent Application Publication No. 2005 / 0218001 A1 discloses a current measurement device that measures the current in a conductor that supplies current to one or more electrolysis cells.

[0003] In a stacked cell type electrolyser in which an alkaline water mixture is fed through a manifold channel to a range of individual cells for the purpose of obtaining electrolysed hydrogen and oxygen, a potential difference will exist between the two cells or half-cells which are adjacent to the current injector plates located at either end of a range of individual cells.

[0004] This potential difference will inevitably generate a current in the electrolyte fluid in the manifold due to the alkaline nature of the electrolyte and the low ohmic resistance in the fluid. Although it would be of interest to know the magnitude of the current flowing through the channel, the large potential difference, the corrosive nature of the alkaline fluid, and the pressure difference between the ambient and the vessel in the stack make direct galvanic measurement impractical. Therefore, an alternative to direct galvanic measurement of the current flowing in the electrolyte manifold channels is desirable. Summary of the Invention [Means for solving the problem]

[0005] The present invention comprises a method for measuring current in an electrolytic cell stack comprising the steps of providing at least one sensor comprising an element responsive to the presence of magnetic flux and / or magnetic flux changes adjacent an electrolyte manifold channel outside a current injector plate of the electrolytic cell stack, ensuring an electrical or wireless connection between the sensor and a recording and / or display device, applying a potential difference between two current injector plates with a cell stack disposed therebetween, capturing at least one signal value indicative of the magnetic flux and / or magnetic flux changes at the sensor location by the at least one sensor, and making the at least one signal value available for storage and / or transmission to a remote location via a wired and / or wireless connection.

[0006] The electrolyte in the manifold channels can carry significant current when the stack is energized by current passing from one current injector plate to the other through the confines of the individual electrolyzer cells present between the two current injector plates. The current in the manifold channels can be measured at a location just outside the cell stack, opposite the current injector plate through which the electrolyte and gas manifold channels are passed. Current measured at this location may indicate undesirable conditions in the stack as it passes through or leaves the stack, and it is important that it is registered. The end plates are usually made of iron and may be more or less directly tied to a zero potential such as earth. In any case, the various channels passing through the end plates are not necessarily electrically insulated from them. Thus, currents may pass through the end plates and measuring these currents is difficult. The presence of a sensor responsive to magnetic fields and / or magnetic field changes near the manifold channel outside the current injector plates in the stack allows for sensing of magnetic fields caused by current in the electrolyte, which may result in an indication of current flux and / or current flux changes in the electrolyte passing in the manifold channel. The current in the channel may be observed between a first cell fluid connection and a first short circuit between the channel fluid and the end plate. If the channel remains electrically isolated from the end plate, the current in the channel may also be observed outside the end plate by using a sensor as described. The resulting current indication may be transmitted from the sensor location to a remote location for recording and / or display. The current indication signal may then be made available to a control unit of the plant, which may trigger automatic changes in response to detected current levels or changes in current levels.

[0007] In one embodiment, an insulating plate is fabricated with a pocket and positioned adjacent to the back side of the current injector, whereby the pocket is positioned to surround at least one of the electrolyte manifold channels, the oxygen manifold channels, or the hydrogen manifold channels at a predetermined distance from the channels leaving a rim of material around each channel, whereby at least one sensor is inserted into the pocket.

[0008] The insulating plate is present to ensure that the potential of the current injector, which is connected to a source of DC power during electrolysis, is also not present on the end plates. In a pressurized stack, the end plates are biased towards each other to counterbalance the internal pressure within the stack and contain the various products therein. The insulating plate will therefore be subjected to a pressurized force and must be strong enough to maintain the pressurized force between the end plates and the current injector plate. Working with this insulating plate and embedding sensitive electronics in it therefore requires careful consideration of both mechanical and electrical complexities.

[0009] In one embodiment, the pocket is located adjacent to the current injector plate so that the insulating plate is complete and uninterrupted with respect to the end plate, in which case the pocket can extend into the current injector plate in a recess provided at the end of the insulating plate adjacent to the insulating plate, where the sensor is located around the channel being observed, in which case the overall thickness of the insulating plate does not need to be changed.

[0010] In another embodiment, the pocket is provided adjacent the end plate so that the insulating plate is complete at the face that abuts the current injector plate. In this embodiment, the pocket may extend into a recess adjacent the insulating plate or may be formed in the end plate around the observed channel, in which case the overall thickness of the insulating plate need not be changed.

[0011] In one embodiment, signals indicative of current or current changes in all of the catholyte manifold channels, anolyte manifold channels, hydrogen manifold channels, and oxygen manifold channels of the stack are captured and made available for storage and / or transmission.

[0012] Preferably, the currents passing through both the electrolyte manifold channel and both the hydrogen and oxygen manifold channels are monitored. This allows for more sensitive and accurate measurements. Also, in some electrolyzer types, the anolyte and catholyte have separate flow paths, and the current levels in each of the manifold channels must be observed to capture the currents that flow between the anolyte and catholyte and do not contribute to the electrolysis process. Current densities are also captured in the manifold channels that exhaust the product gases from the electrolyzer stack, because in alkaline water electrolyzers, these manifold channels carry a mixture of anolyte and oxygen and a mixture of catholyte and hydrogen, respectively, and due to the presence of electrolyte in these two channels, current densities are also present in the channels. The magnitude of these currents may also provide important information about the current conditions in the stack during electrolysis, and feedback mechanisms can be realized based on such data. This may result in more optimized operation of multiple stacks, as entities such as current supply and electrolyte flow in the individual stacks are adjusted.

[0013] In one embodiment, an O-ring or similar gasket device is pressed against the material of the material rim around each of the manifold channels, so that the O-ring is adapted to be present in the U-shaped groove of the current injector plate, or in the U-shaped groove of the end plate, and / or in the U-shaped groove of the insulator plate. The O-ring serves to maintain the pressure in the electrolyte manifold channel of the pressurized electrolytic cell. This pressure can be 40 bar or more. It is therefore required that the material rim around the electrolyte manifold has sufficient strength to withstand the radial pressure from within the channel. The material rim therefore needs to have a certain thickness and is gasketed against the adjacent element, whether it be a current injector plate or an end plate. This gasket is ensured by the O-ring. This ring is made of a suitable flexible material and is preferably inserted at least partially into the groove of the current injector plate / end plate to ensure its position. Alternatively or additionally, the gasket is positioned in the groove of the insulator plate.

[0014] In one embodiment of the method, the sensor is disposed with a core material having a high magnetic permeability and exposed to a magnetic field generated by a current in the manifold channel, and at least one of a Hall element and a coil is provided adjacent to the core material, and an electrical response signal emitted from the Hall element and / or the coil is made available for storage and / or transmission to a remote location.

[0015] By having a magnetic core with high magnetic permeability, a coil and a Hall sensor, a zero-flux type sensor can be provided, whereby a current is fed to a coil wound on the core, which counteracts the magnetic flux generated by the current in the channel. The resulting combined magnetic flux in the core is measured by a Hall element, which is inserted into a radially shaped slit in the core for this purpose. To keep the signal from the Hall sensor constant, a small circuit containing an amplifier is used, the output signal is the potential on the coil / current through the coil, and this potential must be maintained to obtain an unchanging signal from the Hall sensor. This provides a more precise sensor with high sensitivity over a wide range.

[0016] It is also possible to provide a coil wound around the electrolyte channel and monitor the current and / or potential induced in such coil due to current changes in the electrolyte channel. Such a coil is particularly suitable for monitoring the ripple of the current in the electrolyte channel. In theory, by continuously integrating the signal from such a coil from the outset, it may be possible to obtain a reliable value of the direct current level in the channel.

[0017] In one embodiment, the pocket extends through the thickness of the insulator plate to a depth of no more than 4 / 5 of the thickness of the insulator plate.

[0018] Usually the insulator plate does not need to be thick because the potential difference between the end plate and the current injection plate is small, but to accommodate the sensor the plate may need to be thickened or made from a material with greater strength and improved electrical insulation. In any case, however, a reasonable proportion of the plate thickness must remain uncompromised by the provision of the pocket to ensure both strength and electrical insulation in the area of ​​the pocket. It is therefore recommended that a certain proportion of the thickness be set aside for this purpose, so that the depth of the pocket is no more than 4 / 5 of the thickness of the insulator plate.

[0019] In one embodiment, a pocket is milled into the insulator plate prior to insertion of the sensor.

[0020] This is particularly advantageous where the insulator plate is first cut from an endless lane of material.

[0021] The pocket may be open radially, preferably toward the periphery in the general direction where the distance between the manifold channel and the radial surface of the insulator plate is smallest. This embodiment allows for easy replacement of the sensor.

[0022] In one embodiment, in a step prior to assembling the stack, the void around the sensor is filled with a hardenable resin, thus embedding the insulator plate material in the pocket and the sensor and transmitting element in the resin.

[0023] This embodiment provides excellent protection for the sensor and transmitter on the one hand, but on the other hand makes it impossible to replace or disassemble the sensor and transmitter. This embodiment also allows the rim of material around the manifold channel to be radially thin, since the pressurized forces from the fluid in the channel are absorbed by the hardened resin and the sensor itself, and then dispersed radially away from the channel. "Thin" in this context means that the rim of material does not by itself have sufficient strength to withstand the radial pressure from the fluid in the channel when pressurized.

[0024] In one embodiment, the sensor element is inserted into the pocket before, during, or after assembly of the stack.

[0025] This method facilitates providing the stack with sensors that can be accessed and removed from the stack or inserted into the stack: if the pocket is not open to the environment, insertion is only possible before or during assembly of the stack, whereas in an open pocket configuration, insertion is possible at any time.

[0026] In a further embodiment, the invention includes an electrolytic cell having a stack of cells with catholyte and anolyte manifolds embedded in the stack adapted to supply catholyte and anolyte to respective catholyte and anolyte cell chambers, the catholyte chamber further comprising a cathode adapted to release hydrogen and the anolyte chamber comprising an anode adapted to release oxygen, wherein an electrolyte comprising alkaline water is supplied through the respective electrolyte manifolds, wherein the gas and electrolyte manifolds are provided and adapted for capture of generated gases.Preferably, a pocket is provided around at least one of the electrolyte input manifold channel, the oxygen output manifold channel, the hydrogen output manifold channel and positioned a predetermined distance from the respective channels and disposed within an insulator plate disposed between an end plate and a current injector plate at one end of the stack, whereby the pocket is adapted to accommodate a sensor.

[0027] A pocket of this nature allows a sensor, such as a sensor responsive to a magnetic field, to reside therein and be sufficiently close to the manifold channel to sense any current that may be passing through the channel. Other types of sensors, such as microphones, accelerometers, thermocouples, etc., may also be provided in the pocket to allow for monitoring other properties, such as sound and / or vibration levels, temperature, etc. Since the insulator present between the end plates and the current injector plate is subject to high pressures, it is not obvious that a pocket would be provided therein to hold any type of sensor. Surprisingly, it has been found that by slightly increasing the thickness of the insulator plate, it is possible to include a variety of types of sensors therein.

[0028] In one embodiment, the insulator plate is made of two plates mated face to face, one of the plates including a notch corresponding to the pocket, and an annular element around the channel enclosed by the pocket. In some cases, the two insulator plates and the annular element are glued and / or welded together such that fluid does not penetrate their intersection when pressurized between the end plate and the current injector plate. In such an embodiment, the pocket may be stamped out of the plate element, making it quick and easy to manufacture.

[0029] In one embodiment, at least one magnetic flux and / or magnetic flux change responsive touchless sensor is disposed within the pocket, whereby the sensor is adapted to record values ​​indicative of current density and / or current density changes within the respective manifold channel, whereby further a transmitting element is provided within the pocket along with the sensor for wireless or wired transmission of the recorded values.

[0030] The magnetic flux can be recorded by an element such as a Hall sensor. Additionally, a coil may be used to record changes in magnetic flux. If a coil is provided and has multiple windings around the manifold channel, any changes in the current level in the channel can be recorded as an electrical potential. One or the other or both of these elements may be provided in the pocket along with a transmitting element such as an amplifier connected to a wired or wireless transmitter.

[0031] In a preferred embodiment, the pocket surrounds the manifold electrolyzer channel and is at least partially open to the periphery.

[0032] If an opening is provided, it may extend along a radial surface of the insulating plate and allow access to the pocket from the outside, allowing sensors, amplifiers wired connections / wireless transmitters to be inserted and removed from the pocket without disassembling the electrolyzer stack.

[0033] In a preferred embodiment, the sensor includes a Hall element and at least one of a highly permeable magnetic material and a coil.

[0034] The core is usually made of a magnetic material with high magnetic permeability and is used to confine and guide the magnetic field lines. It is usually made of a ferrimagnetic metal such as iron or a ferrimagnetic compound such as ferrite. Due to its high magnetic permeability compared to the surrounding material, the magnetic field lines are concentrated in the core material. With a Hall element, the magnetic flux can be measured in the electrolyte channel, but to retain an improved signal-to-noise ratio and a larger measurement window, the Hall element is preferably inserted in a core made as described that surrounds the channel leaving only a narrow gap for the Hall sensor. In this arrangement, the magnetic flux lines originating from the current in the channel are highly concentrated in the Hall element. It is further advantageous to provide a coil around at least a part of the core, so that the current in the coil can cancel the magnetic flux originating from the current in the channel. This makes it possible to provide a zero magnetic flux sensor capable of high accuracy measurements over a wide measurement range.

[0035] In embodiments of the present invention, the predetermined distance is preferably sufficient to contain the pressure within the channel.

[0036] In this embodiment, the predetermined distance between the inner channel surface and the surface of the pocket closest to the channel is sufficient for the insulator plate material to maintain its shape and position when pressure is increased within the channel, such that an O-ring or other gasket device between the insulator plate and the opposing surface remains seated within its groove without the possibility of leakage.

[0037] In one embodiment, a sensor surrounds each channel and the pocket is filled with a hardenable resin, which may be provided between the sensor and / or sensor components and the pocket walls.

[0038] In this embodiment, either the sensor body or the hardenable resin provides the reinforcing means so that even if the material rim between the pocket and the channel is not strong enough to contain the pressure by itself, the stress in the rim is countered by tensioning the sensor and / or the resin around the sensor. In this way, the predetermined distance outlining the size of the rim can be kept relatively small so that the pressure in the channel is transferred through the material rim and the sensor and / or the resin to the surrounding portion of the insulator plate. Thus, any gasketing means such as an O-ring will remain in place and provide the desired gasketing even if the pressure in the channel exceeds the pressure resistance of the material rim.

[0039] Various exemplary and non-limiting embodiments, both in terms of structure and method of operation, together with additional objects and advantages thereof, will be best understood from the following description of certain exemplary and non-limiting embodiments, when read in conjunction with the accompanying drawings. In the above embodiments, it is taken for granted that the sensor is not subject to pressure in the channel. However, it is also possible to place the sensor in the pressurized region and the O-ring outside the pocket. Such an arrangement would preclude a larger opening from the pocket to the surroundings, which generally does not present a significant advantage.

[0040] In this document, the verbs "comprise" and "include" are used as open limitations that do not exclude or require the presence of unrecited features. Features recited in the dependent claims are mutually freely combinable, unless otherwise expressly stated. Furthermore, it is to be understood that the use of "a" or "an", i.e. the singular form, throughout this document does not exclude a plurality.

[0041] In the following, the invention will be described in more detail with reference to the embodiments illustrated by the enclosed figures, in which it is emphasized that the illustrated embodiments are used for illustrative purposes only and should not be used to limit the scope of the invention. [Brief description of the drawings]

[0042] [Figure 1] 1 shows a three-dimensional view of a portion of an insulating plate having a pocket. [Diagram 2] FIG. 1 is a plan view of an insulation plate with milled pockets. [Diagram 3] 3 is an enlarged plan view of a region D in FIG. 2. FIG. [Figure 4] 4 shows a cross-sectional view taken along line FF shown in FIG. 3. [Diagram 5] FIG. 1 is a cross-sectional view of a prior art electrolytic cell. [Figure 6] FIG. 6 is an enlarged view of a portion of the electrolytic cell shown in FIG. [Figure 7] FIG. 7 is an enlarged view of a portion of the electrolytic cell shown in FIG. [Figure 8] 1 shows in schematic form the basic components of the sensor. [Figure 9] The sensor shown in FIG. 8 is equipped with a radio transmitter. [Figure 10] A schematic diagram of the flow volume within the cell stack 1 is shown. [Figure 11] 11. It is the same as FIG. 10, but with stripes instead of colors, and therefore, throughout this description, any reference to FIG. 10 is also valid for FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] In Fig. 5 a prior art electrolytic cell 1 is shown in a three-dimensional cross-section, in which a series of cell frames 2 are held under axial pressure between two end plates 3. A current injector plate 4 is arranged on each end plate 3, and each cell frame 2 is stacked between the two current injector plates 4. The alternating cell frames are associated with respective bipolar plates 30 and diaphragms 29, as known in the art, which can be seen diagrammatically in Fig. 10. Also shown in this figure are the anolyte chamber 24 and the cathode chamber 25, as well as the cathode 26 and anode 27. Also shown are the individual cells 28 and the extension of the entire stack 1 of cells.

[0044] In Figure 5, the proximal end plate 3 is shown with four channels axially extending therethrough: anolyte and catholyte input channels 6, each on one side, and oxygen and hydrogen outlet channels 7, each on the other side. One of the oxygen and hydrogen outlet channels 7 is shown in enlarged cross-sectional view in Figure 6, which allows the insulating plate 8 between the end plate 3 and the current injector plate 4 to be seen.

[0045] In Fig. 7 an enlarged view of the channel of Fig. 6 is shown, which also shows how the channel 7 passes axially through the insulating plate 8. As can further be seen in this figure, an O-ring 15 is provided in the O-ring groove 14 of the current injector plate. Furthermore, the groove 9 of the insulator plate is shown, which is also provided with an O-ring 15. The two O-rings 15, one on each side of the insulating plate 8, ensure a leak-free connection through the insulating plate 8. A somewhat similar arrangement is provided for an insulator plate with a pocket 10 according to the invention, which is provided with an O-ring groove 9, in which an O-ring can be seated and pressed around the channels 6, 7 against the rim 5.

[0046] An enlarged cross section of an insulator plate 8 according to an embodiment of the invention is shown in figure 4. Grooves 9 are provided in the insulator plate 4 and / or the end plates and / or the current injector plates.

[0047] As further seen in FIGS. 6 and 7, a channel bushing 16 is inserted through the end plate, with an O-ring in groove 9 in the insulating plate contacting the end of the channel bushing 16.

[0048] In the three-dimensional view of a portion of an insulating plate 8 according to an embodiment of the invention in FIG. 1, pockets 10 as well as channels 7, 6 are visible, around each channel 6, 7, a material rim 5 of the insulating plate 8 is left in the thickness of the original insulating plate. This material rim 5 may include a groove 9, as best seen in FIG. 4, in which an O-ring (not shown in FIG. 4) can be fitted, which O-ring serves as a gasket means facing the abutment element - the channel bushing 6 or the current injector plate 4. In FIG. 1, a groove is not disclosed, which may alternatively be provided in the abutment element - the channel bushing 16 or the current injector plate 4 - to fix the O-ring.

[0049] In figures 2, 3 and 4 a sensor 11 is shown diagrammatically inside the pocket 10. The sensor 11 is adapted to react to the presence of a magnetic field or magnetic field changes present at this location due to the channels 7,6 and the currents that may pass through the channels 7,6 whenever the electrolytic cell is powered up by the presence of a DC potential difference between the two current injector plates 4 in the presence of electrolyte in the cell and in the channels 6,7.

[0050] The sensor 11 may output an electrical signal such as a current or a potential. In FIG. out5. This signal may be digitized and transferred in any conventional manner, such as by radio transmitter 22 (see FIG. 9) or by electrical connection cable, to a recording or display device 17 as disclosed in FIG. 8. An operator or a digital monitoring and automation system may monitor the signal value or possible changes in the signal value, which by itself or in combination with other information about the state of the stack and the processes therein, gives an indication of a desirable or less desirable state. Based on the recorded information from the sensor 11, the operator or the digitizing system may modify the operating conditions of the stack.

[0051] The pocket 10 may be located by scraping away material around the rim 5, and in some cases the pocket 10 has at least one opening 12 facing the periphery. If the opening 12 is wide, as shown in FIG. 1, the entire sensor 11 can be taken out therefrom, even when assembling the stack. As can be seen in FIG. 2, in this embodiment only a narrow opening 12 is provided. Here, only a small part of the sensor, such as the Hall element 13, may be taken out therefrom in case of need for replacement.

[0052] In embodiments such as those shown in Figures 2-4, sensors 11 are provided in each of the anolyte and catholyte channels 6 and the hydrogen and oxygen manifold channels 7. The oxygen and hydrogen outlet manifold channels 7 carry a mixture of electrolyte and generated oxygen and electrolyte and generated hydrogen, respectively. Since the electrolyte portion of such mixtures is conductive, current may also be present in these channels and measured. Note that in some types of electrolyzer stacks, the anolyte and catholyte fluids are the same and mixed in the tank before injection into the stack, so it is only the end points of the respective manifolds, i.e., the cathode chamber or the anode chamber, that determine whether a particular manifold channel is a catholyte or anolyte channel.

[0053] In FIG. 8, a sensor 11 is shown diagrammatically. Sensors of this kind are well known per se and may have different electrical characteristics due to the different electrical circuits of the sensors. However, the sensors follow the same principle, i.e. a core 18 is provided around an electrical lead 19 and a Hall element 13 is inserted in a radial slit opening 20 in the core 18. The core 18 is made of a ferromagnetic material with high magnetic permeability, so that the magnetic field generated around the lead 19 by the passage of an electric current is focused by the core 18 in the slit opening 20. In this way, the Hall element 13 in the slit opening 20 is exposed to a magnetic field strengthened by the current in the lead 19. In the sensor shown in FIG. 8, an electric coil 21 is further wound on the core. This measure allows the current in the electric coil 21 to be selected so as to maintain a predetermined output from the Hall sensor, for example a zero output. The magnitude of the current required for this purpose is a measure of the current passing through the electric lead 19.

[0054] Where the insulating plate 8 is cut from an endless lane of material, it is advantageous to mill the pockets by conventional milling techniques. The insulating plate may also be produced by other manufacturing techniques, such as injection moulding, in which case the pockets are simply made in the usual way as a positive part of one of the mould halves.

[0055] The sensor 11 can be inserted in the pocket before the assembly of the stack, and a hardening resin can be used to fill the void left in the pocket between the sensor and the insulating plate. In this case, the sensor cannot be easily replaced, of course, but it sits well protected in the pocket 10 and is insulated from the seeping electrolyte material, which is chemically very aggressive and at the same time pressurized in the case of an alkaline and pressurized electrolytic cell. In such a case, the material rim 5 shown in FIG. 4 can be made without much consideration of material strength, since the stresses on the rim from the internal pressure of the channel are at least partially supported by the resin and the remaining insulating plate. Furthermore, a reinforcing ring (not shown) may be provided on the outside of the material rim to increase its resilience against the internal pressure of the channel it surrounds. Such a ring may be made of a material containing fibers, such as carbon-carbon composites, aramid fibers, or a metallic composition or a combination thereof.

[0056] In further embodiments, such as that shown in Figure 4, an air gap is left above or around the sensor, and optionally a soft polymer or foam material (not shown) is added to one or more of the air gaps to keep the sensor in place prior to assembly of the stack, allowing the sensor to be removed from the stack, such as for replacement.

[0057] It should be noted that the figures and the above description are simple and schematic depictions of exemplary embodiments, and many of the specific mechanical details have not been shown, as those skilled in the art should be familiar with these details and would only unnecessarily complicate this description. [Explanation of symbols]

[0058] 1 Electrolyzer cell stack 2 Cell Frame 3 End Plate 4 Current Injector Plate 5 Rim Material 6 Anolyte and Catholyte input manifold channels 7 Oxygen and Hydrogen Outlet Manifold Channels 8 Insulation Plate 9 Insulator Plate O-Ring Groove 10 Pocket 11 Sensors 12 Opening 13 Hall element 14 Current injector plate O-ring groove 15 O-ring 16 Channel Bushing 17 Remote recording or display devices 18 cores 19 Electrical Leads 20 Radial slit opening 21 Electric Coil 22 Sending elements 23 RF Performance Indicators 24 Anolyte Chamber 25 Catholyte Chamber 26 Cathode 27 Anode 28 Single Cell 29 Diaphragm 30 Bipolar Plates

Claims

1. A method for measuring current in an electrolyzer cell stack (1), said method comprising: providing at least one sensor (11) on an insulator plate (8) located between an end plate (3) and a current injector plate (4) at one end of said electrolyzer cell stack (1), and within said electrolyzer stack (1) outside said current injector plate (4), said sensor having an element responsive to the presence of magnetic flux and / or magnetic flux changes adjacent to an input or outlet manifold channel (6, 7); ensuring an electrical or wireless connection between said sensor (11) and a recording and / or display device (17); applying a potential difference between two current injector plates (4) with the electrolyzer cell stack (1) placed between them; capturing signal values ​​indicative of magnetic flux and / or flux changes at the sensor location by said at least one sensor (11); making said at least one signal value available for storage and / or transmission to a remote location (17) via said wired and / or wireless connection; A method comprising:

2. 2. The method of claim 1, wherein the insulating plate (8) is fabricated with a pocket (10) and is placed adjacent to the back side of the current injector plate (4), whereby the pocket (10) is positioned to surround at least one of the anolyte or catholyte input manifold channel (6), the oxygen or hydrogen outlet manifold channel (7) at a predetermined distance from said channel, leaving a material rim (5) around the periphery of said respective channel, whereby the at least one sensor (11) is inserted into the pocket (10).

3. 2. The method of claim 1, wherein signals indicative of current or current changes in all of the anolyte input manifold channels (6), catholyte input manifold channels (6), oxygen outlet manifold channels (7), and hydrogen outlet manifold channels (7) of the cell stack (1) are captured and made available for storage and / or transmission.

4. 3. The method according to claim 2, characterized in that an O-ring (15) or similar gasket device is pressed against the material rim (5) around each of the manifold channels (6, 7), whereby the O-ring is adapted to reside in a U-shaped groove (14) of the current injector plate (4), or to reside in a U-shaped groove of an end plate, and / or to reside in a U-shaped groove of the insulating plate (9).

5. 3. The method of claim 2, characterized in that the sensor (11) is placed in the pocket (10) by a core (18) having high magnetic permeability, whereby it is exposed to a magnetic field generated by a current in the respective manifold channel (6, 7), and at least one of a Hall element (13) and an electric coil (21) is provided adjacent to the core (18), whereby an electric response signal emitted from the Hall element (13) and / or the electric coil (21) is made available for storage and / or transmission to a remote location.

6. 2. A method according to claim 1, characterized in that the pockets (10) are provided in the thickness direction of the insulator plate (8) to a depth of not more than 4 / 5 of the thickness of the insulator plate.

7. 2. A method according to claim 1, characterized in that the pocket (10) is milled into the insulator plate (8) before the insertion of the sensor (11).

8. 2. The method according to claim 1, characterized in that in a step prior to the assembly of the electrolyzer cell stack (1), the void around the sensor (11) is filled with a hardening resin, so that the insulator plate material around the pocket (10) and the sensor (11) and transmitting element are embedded in the resin.

9. 2. The method of claim 1, wherein the sensor (11) is inserted into the pocket (10) before, during or after assembly of the electrolyzer cell stack (1).

10. An electrolyzer (1) comprising a stack of cells, embedded in said stack are catholyte and anolyte input manifolds (6) adapted to supply catholyte and anolyte to respective catholyte and anolyte cell chambers (24, 25), the catholyte chamber (24) further comprising a cathode (26) adapted to release hydrogen and the anolyte chamber (25) comprising an anode (27) adapted to release oxygen, wherein an electrolyte comprising alkaline water is supplied through the respective manifolds (6), wherein gas and electricity are 1. An electrolytic cell (1) in which a solution manifold (7) is provided and adapted for capturing the gas produced, and a pocket (10) is provided around at least one of the electrolyte manifold channel (6) and the gas and electrolyte manifold channel (7) and is located at a predetermined distance from said channels in an insulator plate (8) arranged between an end plate (3) and a current injector plate (4) at one end of said stack (1), whereby said pocket (10) is adapted to accommodate a sensor (11).

11. 11. The electrolytic cell according to claim 10, characterized in that at least one magnetic flux and / or magnetic flux change responsive touchless sensor (11) is arranged in the pocket (10), whereby the sensor (11) is adapted to record values ​​indicative of current density and / or current density changes in the respective manifold channels (6, 7), whereby furthermore a transmitting element (22) for wireless or wired transmission of the recorded values ​​is provided in the pocket (10) together with the sensor (11).

12. 11. An electrolytic cell according to claim 10, characterized in that the pocket (10) surrounds the manifold channels (6, 7) and is at least partially open to the periphery.

13. 12. An electrolytic cell according to claim 11, characterized in that the sensor (11) comprises a Hall element (13) and at least one of a material with high magnetic permeability, such as a core (18), and a coil (12).

14. 11. The electrolytic cell of claim 10, wherein the predetermined distance is sufficient to contain pressure within the channel.

15. 12. An electrolytic cell according to claim 11, characterized in that the sensors (11) surround the respective channels (6, 7) and that the pockets (10) are filled with a hardenable resin provided between the sensors and / or sensor components and the pocket walls.

Images