Electrochemical reactor and method for producing electrochemical reactor

Abstract

The invention relates to an electrochemical reactor for a hybrid redox flow battery, comprising at least one cell (1). The cell (1) comprises an electrode support (11), a first electrode (12) supported by the electrode support (11), a first flow divider (13), a membrane (14) arranged in the first flow divider (13), a second flow divider (15), a second electrode (16) arranged in the second flow divider (15), a first gasket (17) arranged between the electrode support (11) and the first flow divider (13) for creating a fluid-tight seal, the first gasket (17) being screen printed, a second gasket (18) arranged between the first flow divider (13) and the second flow divider (15) for creating a fluid-tight seal, the second gasket (18) being screen printed. The invention also relates to a method for producing an electrochemical reactor.

Description

[0001] ELECTROCHEMICAL REACTOR AND METHOD FOR PRODUCING ELECTROCHEMICAL REACTOR

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to an electrochemical reactor and more particularly to an electrochemical reactor that can be used in a hybrid redox flow battery. The present invention further concerns a method for producing such an electrochemical reactor.

[0004] BACKGROUND OF THE INVENTION

[0005] Advantages of redox flow batteries come down to their high cycle stability, high- scalability, and low cost. In such batteries, the systems power comes from the cells and stacks, and the energy is stored in the electrolyte which contains a dissolved active species, with the species reacting on the electrode surface in order to generate power.

[0006] Currently one of the primary cost drivers for redox flow battery systems comes down to the stack assembly and material costs. One of the primary technical challenges when assembling stacks is the successful containment and separation of the electrolytes. This is typically achieved through the use of gasket sheets that are die cut and then used to seal through compression of the stack. This operation has a high wastage rate due to sealing only being required on the perimeter of the cell. Further, these materials often add significant thickness.

[0007] Additionally, these gasket materials often do not survive repeated compression and decompression cycles that are known to occur during the operation of a redox flow battery, leading to a gradual loss of sealing quality over time.

[0008] Other methods for sealing involve the usage of welding techniques such as laser welding, friction welding, ultrasonic welding, and thermal welding. However, these techniques can only be applied to specific material groupings and are inflexible due to their high setup and calibration requirements to achieve repeated and consistent sealing, and therefore slowing the production process down significantly and reducing the possibility for rapid changes and prototyping. BRIEF DESCRIPTION OF THE INVENTION

[0009] An object of the present invention is to provide an electrochemical reactor for a hybrid redox flow battery. Another object of the present invention is to provide a method for producing an electrochemical reactor for a hybrid redox flow battery.

[0010] The objects of the invention are achieved by the electrochemical reactor and the method which are characterized by what is stated in the independent claims. The preferred embodiments of the invention are disclosed in the dependent claims.

[0011] The invention is based on the idea of providing an electrochemical reactor for a hybrid redox flow battery, comprising at least one cell; wherein the cell comprises an electrode support having a first surface and a second surface opposite the first surface, and arranged to support an electrode; the cell comprises a first electrode arranged in the electrode support; the cell comprises a first flow divider having a first surface and a second surface opposite the first surface, arranged to support a membrane, and comprising an opening extending from the first surface to the second surface, an inlet for electrolyte,

[0012] - an outlet for electrolyte, and

[0013] - a flow channel providing a fluid connection for electrolyte between the inlet and the outlet via the opening; the first surface of the electrode support is facing the second surface of the first flow divider; the cell comprises a membrane arranged in the first flow divider; the cell comprises a second flow divider having a first surface and a second surface opposite the first surface, arranged to support an electrode, and comprising

[0014] - an opening extending from the first surface to the second surface, an inlet for electrolyte, an outlet for electrolyte, and a flow channel providing a fluid connection for electrolyte between the inlet and the outlet via the opening; the first surface of the first flow divider is facing the second surface of the second flow divider; the cell comprises a second electrode arranged in the second flow divider; the cell comprises a first gasket arranged between the first surface of the electrode support and the second surface of the first flow divider for creating a fluid-tight seal between the electrode support and the first flow divider, the first gasket being screen printed; the cell comprises a second gasket arranged between the first surface of the first flow divider and the second surface of the second flow divider for creating a fluid-tight seal between the first flow divider and the second flow divider, the second gasket being screen printed; the electrode support, the first electrode, the first flow divider, and the membrane define a first cell inner space, the first cell inner space being in a fluid connection with the flow channel of the first flow divider; the first flow divider, the membrane, the second flow divider, and the second electrode define a second cell inner space, the second cell inner space being in a fluid connection with the flow channel of the second flow divider; and

[0015] - the second cell inner space is separated from the first cell inner space by the membrane.

[0016] The invention is also based on the idea of providing a method for producing an electrochemical reactor for a hybrid redox flow battery, wherein the method comprises

[0017] - providing an electrode support having a first surface and a second surface opposite the first surface, and arranged to support an electrode; providing a first electrode in the electrode support; providing a first flow divider having a first surface and a second surface opposite the first surface, arranged to support a membrane, and comprising an opening extending from the first surface to the second surface, an inlet for electrolyte, an outlet for electrolyte, and a flow channel providing a fluid connection for electrolyte between the inlet and the outlet via the opening; providing a membrane in the first flow divider; providing a second flow divider having a first surface and a second surface opposite the first surface, arranged to support an electrode, and comprising an opening extending from the first surface to the second surface, an inlet for electrolyte,

[0018] - an outlet for electrolyte, and

[0019] - a flow channel providing a fluid connection for electrolyte between the inlet and the outlet via the opening; providing a second electrode in the second flow divider; forming a first gasket by screen printing gasket material on the first surface of the electrode support or on the second surface of the first flow divider; after forming the first gasket and providing the first electrode in the electrode support, connecting the first surface of the electrode support and the second surface of the first flow divider with the first gasket to obtain a fluid-tight seal between the electrode support and the first flow divider, and to form a first cell inner space defined at least by the electrode support, the first electrode, and the first flow divider; forming a second gasket by screen printing gasket material on the first surface of the first flow divider or on the second surface of the second flow divider; and after forming the second gasket, connecting the first surface of the first flow divider and the second surface of the second flow divider with the second gasket to obtain a fluid-tight seal between the first flow divider and the second flow divider, and to form a second cell inner space defined at least by the first flow divider, the membrane, and the second flow divider. An advantage of the invention is that the costs for producing the electrochemical reactor is reduced due to the utilization of screen printing for forming the gaskets to seal the parts of the reactor. It also results in a faster assembly and the ability to increase the modularity and customizability of the reactor without the need for extensive retooling.

[0020] The screen printing allows for rapid changing of the gasket thickness and geometry by changing the parameters of the silk screen, allowing for dynamic correction of gasket requirements based on raw material feedstock. Additionally, this results in near zero wastage as gasket material is only applied to the relevant areas of the halfcells.

[0021] BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Below, the invention is described in detail with reference to the enclosed drawings, in which

[0023] Figure 1 is a schematic side view of an electrochemical reactor according to some embodiments of the invention;

[0024] Figure 2a is a schematic side view of an electrode support according to some embodiments of the invention;

[0025] Figure 2b is a schematic side view of an electrode support according to some embodiments of the invention;

[0026] Figure 3 is a schematic side view of a first flow divider according to some embodiments of the invention;

[0027] Figure 4 is a schematic side view of a second flow divider according to some embodiments of the invention;

[0028] Figure 5 is a schematic side view of an electrochemical reactor according to some embodiments of the invention;

[0029] Figure 6 is a schematic side view of an electrode support and a first electrode according to some embodiments of the invention;

[0030] Figure 7 is a schematic side view of a second flow divider and a second electrode according to some embodiments of the invention; Figure 8 is a schematic side view of a first flow divider and a membrane according to some embodiments of the invention;

[0031] Figure 9 is a schematic side view of a first flow divider, a membrane and a turbulence promoter according to some embodiments of the invention;

[0032] Figure 10 is a schematic side view of an electrochemical reactor according to some embodiments of the invention;

[0033] Figure 11a is a schematic top view of an electrode support according to some embodiments of the invention;

[0034] Figure lib is a schematic top view of an electrode support according to some embodiments of the invention;

[0035] Figure 12 is a schematic top view of a first flow divider according to some embodiments of the invention; and

[0036] Figure 13 is a schematic top view of a second flow divider according to some embodiments of the invention.

[0037] DETAILED DESCRIPTION OF THE INVENTION

[0038] Electrochemical reactor

[0039] The invention relates to an electrochemical reactor. The electrochemical reactor is useable in a hybrid redox flow battery. In a hybrid redox flow battery, the energy is stored in an electrolyte, which contains dissolved active species. The species reacts on an electrode surface of the battery to generate power.

[0040] The electrochemical reactor comprises at least one cell 1. Preferably, the electrochemical reactor comprises a plurality of cells 1 arranged in a stack. The at least one cell 1 comprises two half-cells that are separated by a membrane. In other words, the two half-cells of the at least one cell 1 have no fluid connection between each other.

[0041] Electrode support

[0042] The cell 1 comprises an electrode support 11. The electrode support 11 has a first surface 111 and a second surface 112 opposite the first surface 111. The electrode support 11 is arranged to support, or hold, an electrode. According to some embodiments, the electrode support 11 comprises a cutout 117, or a recess, for supporting an electrode. In other words, the cutout 117 is arranged to receive the electrode. Preferably, the cutout 117 is arranged in the first surface 111 of the electrode support 11.

[0043] According to some embodiments, the electrode support 11 comprises an opening 113 extending from the first surface 111 to the second surface 112, as exemplified in Figures 2b and lib. This allows the electrode support to act as a flow divider in a situation in which the cell 1 is a part of a stack.

[0044] In these embodiments, the electrode support 11 further comprises an inlet 114 for electrolyte, an outlet 115 for electrolyte, and a flow channel 116 providing a fluid connection for electrolyte between the inlet 114 and the outlet 115 via the opening 113. In other words, the electrolyte is able to flow from the inlet 114 to the outlet 115 through the opening 113. Preferably, the electrode support 11 acts as a manifold for the electrolyte.

[0045] According to some embodiments, the inlet 114 and the outlet 115 of the electrode support 11 comprise openings penetrating the electrode support 11 from the first surface 111 to the second surface 112, as exemplified in Figures 2b, 5, 6, 10 and lib. The flow channel 116 preferably comprises at least one groove arranged in the second surface 112 of the electrode support 11.

[0046] The inlet 114 and the outlet 115 of the electrode support 11 are arranged to be connected to a first electrolyte reservoir and to a first electrolyte pump (not shown in the figures) for circulating first electrolyte from the first electrolyte reservoir in the flow channel 116 of the electrode support 11.

[0047] In these embodiments, the cutout 117 surrounds the opening 113. In other words, the opening 113 is arranged inside the cutout 117. This means that the cutout 117 overlaps the opening 113. Preferably, the overlap is 0.5 to 10 %, more preferably 1 to 5 %, of the surface area of the first surface 111 of the electrode support 11. This means the material surface of the first surface 111 of the electrode support 11, i.e. excluding the opening 113. According to some alternative embodiments, the electrode support 11 is solid between the first surface 11 and the second surface 12, as exemplified in Figures 1 and 2a. In other words, there is no opening between the first surface 111 and the second surface 112 of the electrode support 11. This allows using the electrode support 11 in a single-cell electrochemical reactor or as an end of a stacked electrochemical reactor.

[0048] First electrode

[0049] The cell 1 comprises a first electrode 12. The first electrode 12 is arranged in the electrode support 11. Preferably, the first electrode 12 is attached to the electrode support 11 to prevent the movement of the first electrode 12 in relation to the electrode support 11.

[0050] According to some embodiments, the first electrode 12 is arranged in the cutout 117 of the electrode support 11, as exemplified in Figures 1, 5, 6 and 10. In other words, the first electrode 12 is circumferentially surrounded by the electrode support 11.

[0051] When the electrode support 11 comprises the opening 113, the first electrode 12 is attached to the electrode support 11 in such a way that flow of electrolyte through the opening 113 is prevented. In other words, the first electrode 12 is sealed to the electrode support 11.

[0052] For example, the first electrode 12 comprises a first electrode plate 121 having a first surface 1211 and a second surface 1212 opposite the first surface 1211, as exemplified in Figure 6. Preferably, the first electrode plate 121 is a bipolar plate.

[0053] According to some embodiments, the first electrode 12 comprises a first conductive felt 122, such as a carbon felt, adhered to the first surface 1211 of the first electrode plate 121, as exemplified in Figures 6 and 10. The purpose of the first conductive felt 122 is to increase the surface area of the first electrode 12 to improve reactions on the first electrode 12 while providing sufficient electronic conduction.

[0054] Preferably, the first conductive felt 122 is adhered to the first electrode plate 121 using screen printed conductive ink, such as carbon ink. The conductive ink needs to have sufficient adhesion properties to be used as an adhesive. Adhering the first conductive felt 122 to the first electrode plate 121 reduces the system overpressure and thereby increasing its efficiency compared to relying on compression to connect the conductive felt to the electrode plate.

[0055] According to some embodiments, the first electrode 12 comprises a screen printed coating provided on the first surface 1211 of the first electrode plate 121. For example, the screen printed coating is a carbon ink coating or a catalyst material coating, such as ionic conductive catalyst material coating. The purpose of the carbon ink coating is to produce a more preferable surface geometry on the first electrode 12 for reactions, such as metal deposition. The purpose of the catalyst material coating is to accelerate reactions on the first electrode 12.

[0056] First flow divider

[0057] The cell 1 comprises a first flow divider 13. The first flow divider 13 has a first surface 131 and a second surface 132 opposite the first surface 131. The first flow divider 13 is arranged to support, or hold, a membrane.

[0058] The first flow divider 13 comprises an opening 133 extending from the first surface 131 to the second surface 132. The opening 133 allows the membrane to be in contact with both of the two half-cells.

[0059] The first flow divider 13 comprises an inlet 134 for electrolyte, an outlet 135 for electrolyte, and a flow channel 136 providing a fluid connection for electrolyte between the inlet 134 and the outlet 135 via the opening 133. In other words, the electrolyte is able to flow from the inlet 134 to the outlet 135 through the opening 133. Preferably, the first flow divider 13 acts as a manifold for the electrolyte.

[0060] According to some embodiments, the inlet 134 and the outlet 135 of the first flow divider 13 comprise openings penetrating the first flow divider 13 from the first surface 131 to the second surface 132, as exemplified in Figures 3, 5, 8, 9 and 12. The flow channel 136 preferably comprises at least one groove arranged in the second surface 132 of the first flow divider 13.

[0061] The inlet 134 and the outlet 135 of the first flow divider 13 are arranged to be connected to a second electrolyte reservoir and to a second electrolyte pump (not shown in the figures) for circulating second electrolyte from the second electrolyte reservoir in the flow channel 136 of the first flow divider 13. The first surface 111 of the electrode support 11 is facing the second surface 132 of the first flow divider 13. Preferably, the first electrode 12 is sandwiched between the electrode support 11 and the first flow divider 13.

[0062] According to some embodiments, the first flow divider 13 comprises a cutout 137, or a recess, for supporting a membrane, as exemplified in Figures 3 and 12. In other words, the cutout 137 is arranged to receive the membrane. Preferably, the cutout 137 is arranged in the first surface 131 of the flow divider 13.

[0063] The cutout 137 surrounds the opening 133. In other words, the opening 133 is arranged inside the cutout 137. This means that the cutout 137 overlaps the opening 133. Preferably, the overlap is 0.5 to 10 %, more preferably 1 to 5 %, of the surface area of the first surface 131 of the first flow divider 13. This means the material surface of the first surface 131 of the first flow divider 13, i.e. excluding the opening 133.

[0064] Membrane

[0065] The cell 1 comprises a membrane 14. For example, the membrane 14 is a porous membrane or an ion exchange membrane. The membrane 14 is also known as a separator because the membrane 14 is used to separate the cathode and the anode of the electrochemical reactor spatially and electrically from each other.

[0066] The membrane 14 must be permeable with respect to specific ions which, for example in a redox flow battery, bring about the conversion of the stored chemical energy into electrical energy.

[0067] For example, the membrane 1 is made of microporous plastic material, such as PVC, PE or PP.

[0068] The membrane 14 is arranged in the first flow divider 13. Preferably, the membrane 14 is arranged in the opening 133 of the first flow divider 13. In other words, the membrane 14 is arranged to prevent the flow of electrolyte through the opening 133 of the first flow divider 13, meaning that the membrane 14 is sealed to the first flow divider 13. According to some embodiments, the membrane 14 is arranged in the cutout 137 of the first flow divider 13, as exemplified in Figures 5, 8, 9 and 10. In other words, the membrane 14 is circumferentially surrounded by the first flow divider 13.

[0069] Typically in redox flow batteries, either porous or ion exchange separators / membranes are employed. In the case of porous separators, their handling is often simplified due to their high thickness and rigidity. However, for ion exchange membranes, that are often supplied as thin film on a roller, the handling is significantly harder.

[0070] According to some embodiments, when the membrane 14 is an ion exchange membrane, the membrane 14 comprises a porous support sheet 141 and a screen printed ion exchange membrane layer 142 provided on a surface of the porous support sheet 141, as exemplified in Figures 8, 9 and 10. For example, the porous support sheet 141 is a nano-porous or micro-porous sheet, or non-woven or woven fabric. Using a screen printed ion exchange membrane layer 142 allows forming the membrane 14 in situ during the production of the cell 1. This prevents the need for handling ion exchange membranes supplied as thin film on a roller. This also removes the need for complex equipment to handle, secure, and seal the ion exchange membrane to the first flow divider 13. Additionally, by changing the properties of the silk screen used during the screen printing process, the ion exchange membrane layer 142 applied can be varied by thickness, which can be used to influence the properties of the redox flow battery. Additionally, the screen printing method allows easy changing of the ionic polymer used without significant changes to the tooling.

[0071] According to some embodiments, the cell 1 comprises a turbulence promoter 21 connected to the membrane 14, as exemplified in Figures 9 and 10. The purpose of the turbulence promoter 21 is to improve the performance of the electrochemical reactor. For example, the turbulence promoter 21 has been adhered to the porous support sheet 141 using the screen printed ion exchange membrane layer 142.

[0072] Second flow divider

[0073] The cell 1 comprises a second flow divider 15. The second flow divider 15 has a first surface 151 and a second surface 152 opposite the first surface 151. The second flow divider 15 is arranged to support, or hold, an electrode. The second flow divider 15 comprises an opening 153 extending from the first surface 151 to the second surface 152. The opening 153 allows the electrode to be in contact with two adjacent half cells of separate cells 1 in a stacked electrochemical reactor.

[0074] The second flow divider 15 comprises an inlet 154 for electrolyte, an outlet 155 for electrolyte, and a flow channel 156 providing a fluid connection for electrolyte between the inlet 154 and the outlet 155 via the opening 153. In other words, the electrolyte is able to flow from the inlet 154 to the outlet 155 through the opening 153. Preferably, the second flow divider 15 acts as a manifold for the electrolyte.

[0075] According to some embodiments, the inlet 154 and the outlet 155 of the second flow divider 15 comprises openings penetrating the second flow divider 15 from the first surface 151 to the second surface 152, as exemplified in Figures 1, 4, 5, 7, 10 and 13. The flow channel 156 preferably comprises at least one groove arranged in the second surface 152 of the second flow divider 15.

[0076] The inlet 154 and the outlet 155 of the second flow divider 15 are arranged to be connected to the first electrolyte reservoir and to the first electrolyte pump or to a third electrolyte pump (not shown in the figures) for circulating first electrolyte from the first electrolyte reservoir in the flow channel 156 of the second flow divider 15.

[0077] The first surface 131 of the first flow divider 13 is facing the second surface 152 of the second flow divider 15. Preferably, the second electrode 16 is sandwiched between the first flow divider 13 and the second flow divider 15.

[0078] According to some embodiments, the second flow divider 15 comprises a cutout 157, or a recess, for supporting an electrode, as exemplified in Figures 4 and 13. In other words, the cutout 137 is arranged to receive the electrode. Preferably, the cutout 157 is arranged in the first surface 151 of the second flow divider 15.

[0079] The cutout 157 surrounds the opening 153. This means that the cutout 157 overlaps the opening 153. Preferably, the overlap is 0.5 to 10 %, more preferably 1 to 5 %, of the surface area of the first surface 151 of the second flow divider 15. This means the material surface of the first surface 151 of the second flow divider 15, i.e. excluding the opening 153. Second electrode

[0080] The cell 1 comprises a second electrode 16. The second electrode 16 is arranged in the second flow divider 15.

[0081] Preferably, the second electrode 16 is arranged in the opening 153 of the second flow divider 15. In other words, the second electrode 16 is arranged to prevent the flow of electrolyte through the opening 153 of the second flow divider 15, meaning that the second electrode 16 is sealed to the second flow divider 15.

[0082] According to some embodiments, the second electrode 16 is arranged in the cutout 157 of the second flow divider 15, as exemplified in Figures 1, 5, 7 and 10. In other words, the second electrode 16 is circumferentially surrounded by the second flow divider 15.

[0083] According to some embodiments, the second electrode 16 comprises a second electrode plate 161 having a first surface 1611 and a second surface 1612 opposite the first surface 1611, as exemplified in Figure 7. Preferably, the second electrode plate 161 is a bipolar plate.

[0084] According to some embodiments, the second electrode 16 comprises a second conductive felt 162, such as a carbon felt, adhered to the second surface 1612 of the second electrode plate 161, as exemplified in Figures 7 and 10. The purpose of the second conductive felt 162 is to increase the surface area of the second electrode 16 to improve reactions on the second electrode 16 while providing sufficient electronic conduction.

[0085] Preferably, the second conductive felt 162 is adhered to the second electrode plate 161 using screen printed conductive ink, such as carbon ink. Adhering the second conductive felt 162 to the second electrode plate 161 reduces the system overpressure and thereby increasing its efficiency compared to relying on compression to connect the conductive felt to the electrode plate.

[0086] According to some embodiments, the second electrode 16 comprises a screen printed coating provided on the second surface 1612 of the second electrode plate 161. For example, the screen printed coating is a carbon ink coating or a catalyst material coating, such as ionic conductive catalyst material coating. The purpose of the carbon ink coating is to produce a more preferable surface geometry on the second electrode 16 for reactions, such as metal deposition. The purpose of the catalyst material coating is to accelerate reactions on the second electrode 16.

[0087] First gasket and second gasket

[0088] The cell 1 comprises a first gasket 17. The first gasket 17 is arranged between the first surface 111 of the electrode support 11 and the second surface 132 of the first flow divider 13 for creating a fluid-tightseal between the electrode support 11 and the first flow divider 13.

[0089] According to some embodiments, the first gasket 17 overlaps with the first electrode 12. This prevents electrolyte from entering from the side of the first surface 1211 of the first electrode 12 to the side of the second surface 1212 of the first electrode 12. In other words, the first gasket 17 seals the first electrode 12 to the electrode support 11.

[0090] The cell 1 comprises a second gasket 18. The second gasket 18 is arranged between the first surface 131 of the first flow divider 13 and the second surface 152 of the second flow divider 15 for creating a fluid-tight seal between the first flow divider 13 and the second flow divider 15.

[0091] According to some embodiments, the second gasket 18 overlaps with the membrane 12. This prevents electrolyte from entering through the opening 133 of the first flow divider 13 past the membrane 14. In other words, the second gasket 18 seals the membrane 14 to the first flow divider 13.

[0092] The first gasket 17 and the second gasket 18 are screen printed. In other words, the first gasket 17 and the second gasket 18 are provided by screen printing gasket material on the first surface 111 of the electrode support or on the second surface 132 of the first flow divider 13, and on the first surface 131 of the first flow divider 13 or on the second surface 152 of the second flow divider 15 and optionally curing the gasket material to form the first gasket 17 and the second gasket 18. Using screen printed gaskets allows forming the gaskets in situ during the production of the cell 1. This results in near zero wastage as the gasket material is only applied to the relevant areas. According to some embodiments, the first gasket 17 and the second gasket 18 comprise ultraviolet curable resin.

[0093] According to some embodiments, the thickness of the first gasket 17 and the second gasket 18 is 20 to 200 gm. Screen printing allows forming thin gaskets. It also allows rapid changing of the thickness and geometry of the gasket by changing the parameters of the silk screen, allowing for dynamic correction of gasket requirements based on raw material feedstock.

[0094] First cell inner space

[0095] The electrode support 11, the first electrode 12, the first flow divider 13, and the membrane 14 define a first cell inner space 19, and they all together form one halfcell of the cell 1.

[0096] The first cell inner space 19 is in a fluid connection with the flow channel 136 of the first flow divider 13. In other words, the first cell inner space 19 is in a fluid connection with the inlet 134 and the outlet 135 of the first flow divider 13. The cell 1 is arranged to allow the flow of electrolyte from the inlet 134 of the first flow divider through the flow channel 136 of the first flow divider 13 to the first cell inner space 19, and from the first cell inner space 19 through the flow channel 136 of the first flow divider 13 to the outlet of the first flow divider 13. In the first cell inner space 19, the electrolyte is in contact with first electrode 12 and the membrane 14.

[0097] Preferably, the electrode support 11 and the second flow divider 15 comprise openings that penetrate the electrode support 11 and the second flow divider 15 and that are in fluid connection with the inlet 134 of the first flow divider 13, creating a fluid connection for the electrolyte. Correspondingly, the electrode support 11 and the second flow divider 15 comprise openings that are in fluid connection with the outlet 135 of the first flow divider 13, creating a fluid connection for the electrolyte.

[0098] According to some embodiments, the first surface 1211 of the first electrode plate 121 is facing the first cell inner space 19. This means that if the first electrode 12 comprises the first conductive felt 122, the first conductive felt 122 is facing the first cell inner space 19. Second cell inner space

[0099] The first flow divider 13, the membrane, the second flow divider 15, and the second electrode 16 define a second cell inner space 20, and they all together form one halfcell of the cell 1.

[0100] The second cell inner space 20 is in a fluid connection with the flow channel 156 of the second flow divider 15. In other words, the second cell inner space 20 is in a fluid connection with the inlet 154 and the outlet 155 of the second flow divider 15. The cell 1 is arranged to allow the flow of electrolyte from the inlet 154 of the second flow divider through the flow channel 156 of the second flow divider 15 to the second cell inner space 20, and from the second cell inner space 20 through the flow channel 156 of the second flow divider 15 to the outlet of the second flow divider 15. In the second cell inner space 20, the electrolyte is in contact with the membrane 14 and the second electrode 16.

[0101] The second cell inner space 20 is separated from the first cell inner space 19 by the membrane 14. In other words, the two half-cells of the cell 1 are separated spatially and electrically from each other by the membrane 14.

[0102] Preferably, the electrode support 11 and the first flow divider 13 comprise openings that penetrate the electrode support 11 and the first flow divider 13 and that are in fluid connection with the inlet 154 of the second flow divider 15, creating a fluid connection for the electrolyte. If the electrode support 11 functions as a flow divider, the corresponding opening is formed by the inlet 114 of the electrode support. Correspondingly, the electrode support 11 and the first flow divider 13 comprise openings that are in fluid connection with the outlet 155 of the second flow divider 15, creating a fluid connection for the electrolyte. If the electrode support 11 functions as a flow divider, the corresponding opening is formed by the outlet 115 of the electrode support.

[0103] According to some embodiments, the second surface 1612 of the second electrode plate 161 is facing the second cell inner space 20. This means that if the second electrode 16 comprises the second conductive felt 162, the second conductive felt 162 is facing the second cell inner space 19. Method

[0104] The invention relates to a method for producing an electrochemical reactor. The electrochemical reactor can be used in a hybrid redox flow battery. Preferably, the electrochemical reactor is an electrochemical reactor as described above.

[0105] The electrochemical reactor comprises at least one cell 1. Preferably, the electrochemical reactor comprises a plurality of cells 1 arranged in a stack. The at least one cell 1 comprises two half-cells that are separated by a membrane.

[0106] Providing electrode support

[0107] The method comprises providing an electrode support 11. The electrode support has a first surface 111 and a second surface 112 opposite the first surface 111. The electrode support is arranged to support, or hold, an electrode.

[0108] According to some embodiments, the electrode support 11 comprises a cutout 117, preferably in the first surface 111, for supporting an electrode. In other words, the cutout 117 is arranged to receive the electrode. Preferably, the cutout 117 is arranged in the first surface 111 of the electrode support 11.

[0109] According to some embodiments, the electrode support 11 comprises an opening 113 extending from the first surface 111 to the second surface 112. This allows the electrode support to act as a flow divider in a situation in which the cell 1 is a part of a stack.

[0110] In these embodiments, the electrode support 11 further comprises an inlet 114 for electrolyte, an outlet 115 for electrolyte, and a flow channel 116 providing a fluid connection for electrolyte between the inlet 114 and the outlet 115 via the opening 113. In other words, the electrolyte is able to flow from the inlet 114 to the outlet 115 through the opening 113. Preferably, the electrode support 11 acts as a manifold for the electrolyte.

[0111] According to some embodiments, the inlet 114 and the outlet 115 of the electrode support 11 comprise openings penetrating the electrode support 11 from the first surface 111 to the second surface 112. The flow channel 116 preferably comprises at least one groove arranged in the second surface 112 of the electrode support 11. In these embodiments, the cutout 117 surrounds the opening 113. In other words, the opening 113 is arranged inside the cutout 117. This means that the cutout 117 overlaps the opening 113. Preferably, the overlap is 0.5 to 10 %, more preferably 1 to 5 %, of the surface area of the first surface 111 of the electrode support 11. This means the material surface of the first surface 111 of the electrode support 11, i.e. excluding the opening 113.

[0112] According to some alternative embodiments, the electrode support 11 is solid between the first surface 11 and the second surface 12. In other words, there is no opening between the first surface 111 and the second surface 112 of the electrode support 11. This allows using the electrode support 11 in a single-cell electrochemical reactor or as an end of a stacked electrochemical reactor.

[0113] Providing first electrode

[0114] The method comprises providing a first electrode 12 in the electrode support 11. In other words, the first electrode 12 is provided as supported in the electrode support 11. Preferably, the first electrode 12 is provided as attached to the electrode support 11 to prevent the movement of the first electrode 12 in relation to the electrode support 11.

[0115] According to some embodiments, providing the first electrode 12 comprises providing the first electrode 12 in the cutout 117 of the electrode support 11. In other words, the first electrode 12 is provided as circumferentially surrounded by the electrode support 11.

[0116] When the electrode support 11 comprises the opening 113, the first electrode 12 is attached to the electrode support 11 in such a way that flow of electrolyte through the opening 113 is prevented. In other words, the first electrode 12 is sealed to the electrode support 11.

[0117] For example, the first electrode 12 comprises a first electrode plate 121 having a first surface 1211 and a second surface 1212 opposite the first surface 1211. Preferably, the first electrode plate 121 is a bipolar plate.

[0118] According to some embodiments, the method comprises screen printing conductive ink, such as carbon ink, on the first surface 1211 of the first electrode plate 121. The conductive ink needs to have sufficient adhesion properties to be used as an adhesive. This step can be performed before providing the first electrode 12 in the electrode support 11, or it can be performed after providing the first electrode 12 in the electrode support 11. The method further comprises adhering a first conductive felt 122, such as a carbon felt, to the first surface 1211 of the first electrode plate 121 with the conductive ink. This step can also be performed before providing the first electrode 12 in the electrode support 11, or it can be performed after providing the first electrode 12 in the electrode support 11. Adhering the first conductive felt 122 to the first electrode plate 121 reduces the system overpressure and thereby increasing its efficiency compared to relying on compression to connect the conductive felt to the electrode plate.

[0119] According to some embodiments, the method comprises screen printing a coating on the first surface 1211 of the first electrode plate 121. This step can be performed before providing the first electrode 12 in the electrode support 11, or it can be performed after the first electrode 12 is provided in the electrode support 11. For example, the coating is a carbon ink coating or a catalyst material coating, such as ionic conductive catalyst material coating. The purpose of the carbon ink coating is to produce a more preferable surface geometry on the first electrode 12 for reactions, such as metal deposition. The purpose of the catalyst material coating is to accelerate reactions on the first electrode 12.

[0120] Providing first flow divider

[0121] The method comprises providing a first flow divider 13. The first flow divider 13 has a first surface 131 and a second surface 132 opposite the first surface 131. The first flow divider 13 is arranged to support, or hold, a membrane.

[0122] The first flow divider 13 comprises an opening 133 extending from the first surface to the second surface. The opening 133 allows the membrane to be in contact with both of the two half-cells.

[0123] The first flow divider 13 comprises an inlet 134 for electrolyte, an outlet 135 for electrolyte, and a flow channel 136 providing a fluid connection for electrolyte between the inlet 134 and the outlet 135 via the opening 133. In other words, the electrolyte is able to flow from the inlet 134 to the outlet 135 through the opening 133. Preferably, the first flow divider 13 acts as a manifold for the electrolyte.

[0124] According to some embodiments, the inlet 134 and the outlet 135 of the first flow divider 13 comprises openings penetrating the first flow divider 13 from the first surface 131 to the second surface 132. The flow channel 136 preferably comprises at least one groove arranged in the second surface 132 of the first flow divider 13.

[0125] The first surface 111 of the electrode support 11 is facing the second surface 132 of the first flow divider 13. Preferably, the first electrode 12 is sandwiched between the electrode support 11 and the first flow divider 13.

[0126] According to some embodiments, the first flow divider 13 comprises a cutout 137, or a recess, for supporting a membrane. In other words, the cutout 137 is arranged to receive the membrane. Preferably, the cutout 137 is arranged in the first surface 131 of the flow divider 13.

[0127] The cutout 137 surrounds the opening 133. In other words, the opening 133 is arranged inside the cutout 137. This means that the cutout 137 overlaps the opening 133. Preferably, the overlap is 0.5 to 10 %, more preferably 1 to 5 %, of the surface area of the first surface 131 of the first flow divider 13. This means the material surface of the first surface 131 of the first flow divider 13, i.e. excluding the opening 133.

[0128] Providing membrane

[0129] The method comprises providing a membrane 14 in the first flow divider 13. In other words, the membrane 14 is provided as supported in the first flow divider 13. Preferably, the membrane 14 is provided as attached to the first flow divider 13 to prevent the movement of the membrane 14 in relation to the first flow divider 13.

[0130] For example, the membrane 14 is a porous membrane or an ion exchange membrane. The membrane 14 is also known as a separator because the membrane 14 is used to separate the cathode and the anode of the electrochemical reactor spatially and electrically from each other. The membrane 14 must be permeable with respect to specific ions which, for example in a redox flow battery, bring about the conversion of the stored chemical energy into electrical energy.

[0131] For example, the membrane 1 is made of microporous plastic material, such as PVC, PE or PP.

[0132] The membrane 14 is arranged in the opening 133 of the first flow divider 13. In other words, the membrane 14 attached to the first flow divider 13 in such a way that the flow of electrolyte through the opening 133 of the first flow divider 13 is prevented. In other words, the membrane 14 is sealed to the first flow divider 13.

[0133] According to some embodiments, providing the membrane 14 comprises providing the membrane 14 in the cutout 137 of the first flow divider 13. In other words, the membrane 14 is provided as circumferentially surrounded by the first flow divider 13.

[0134] Typically in redox flow batteries, either porous or ion exchange separators / membranes are employed. In the case of porous separators, their handling is often simplified due to their high thickness and rigidity. However, for ion exchange membranes, that are often supplied as thin film on a roller, the handling is significantly harder.

[0135] According to some embodiments, when the membrane 14 is an ion exchange membrane, providing the membrane 14 comprises providing a porous support sheet 141. For example, the porous support sheet 141 is a nano-porous or micro-porous sheet, or non-woven or woven fabric. Preferably, the porosity of the porous support sheet is 30 to 150 mesh, more preferably 50 to 130 mesh. In other words, the porosity of the porous support sheet is 30 to 150 openings per square inch, more preferably 50 to 130 openings per square inch. This is to achieve a desired thickness for the ion exchange membrane.

[0136] Providing the membrane 14 further comprises screen printing ion exchange polymer dissolved in a solvent on the porous support sheet 141, and allowing the solvent to evaporate to form an ion exchange membrane layer 142 on the porous support sheet 141. Preferably, the concentration of the ion exchange polymer dissolved in the solvent is 5 to 20 wt. %, based on the total weight of the solution. Preferably the thickness of the ion exchange membrane layer 142 is 5 to 100 gm, more preferably 10 to 40 gm. Screen printing the ion exchange membrane layer 142 allows forming the membrane 14 in situ during the production of the cell 1. This prevents the need for handling ion exchange membranes supplied as thin film on a roller. This also removes the need for complex equipment to handle, secure, and seal the ion exchange membrane to the first flow divider 13. Additionally, by changing the properties of the silk screen used during the screen printing process, the ion exchange membrane layer 142 applied can be varied by thickness, which can be used to influence the properties of the redox flow battery. Additionally, the screen printing method allows easy changing of the ionic polymer used without significant changes to the tooling.

[0137] The ion exchange polymer can be screen printed on the porous support sheet 141 before the porous support sheet 141 is provided in the first flow divider 13. Alternatively, the porous support sheet 141 is provided in the first flow divider 13 before screen printing the ion exchange polymer on the porous support sheet 141.

[0138] According to some embodiments, the method comprises providing a turbulence promoter 21 in connection with the membrane 14. Preferably, the turbulence promoter is provided after providing the membrane 14 in the first flow divider 13. The purpose of the turbulence promoter 21 is to improve the performance of the electrochemical reactor. For example, the turbulence promoter 21 is adhered to the porous support sheet 141 using the screen printed ion exchange membrane layer 142.

[0139] Providing second flow divider

[0140] The method comprises providing a second flow divider 15. The second flow divider 15 has a first surface 151 and a second surface 152 opposite the first surface 151. The second flow divider 15 is arranged to support, or hold, an electrode.

[0141] The second flow divider 15 comprises an opening 153 extending from the first surface to the second surface. The opening 153 allows the electrode to be in contact with two adjacent half cells of separate cells 1 in a stacked electrochemical reactor.

[0142] The second flow divider 15 comprises an inlet 154 for electrolyte, an outlet 155 for electrolyte, and a flow channel 156 providing a fluid connection for electrolyte between the inlet 154 and the outlet 155 via the opening 153. In other words, the electrolyte is able to flow from the inlet 154 to the outlet 155 through the opening 153. Preferably, the second flow divider 15 acts as a manifold for the electrolyte.

[0143] According to some embodiments, the inlet 154 and the outlet 155 of the second flow divider 15 comprise openings penetrating the second flow divider 15 from the first surface 151 to the second surface 152. The flow channel 156 preferably comprises at least one groove arranged in the second surface 152 of the second flow divider 15.

[0144] The first surface 131 of the first flow divider 13 is facing the second surface 152 of the second flow divider 15. Preferably, the membrane 14 is sandwiched between the first flow divider 13 and the second flow divider 15.

[0145] According to some embodiments, the second flow divider 15 comprises a cutout 157, or a recess, for supporting an electrode. In other words, the cutout 157 is arranged to receive the electrode. Preferably, the cutout 157 is arranged in the first surface 151 of the second flow divider 15.

[0146] The cutout 157 surrounds the opening 153. This means that the cutout 157 overlaps the opening 153. Preferably, the overlap is 0.5 to 10 %, more preferably 1 to 5 %, of the surface area of the first surface 151 of the second flow divider 15. This means the material surface of the first surface 151 of the second flow divider 15, i.e. excluding the opening 153.

[0147] Providing second electrode

[0148] The method comprises providing a second electrode 16 in the second flow divider 15. In other words, the second electrode 16 is provided as supported in the second flow divider 15. Preferably, the second electrode 16 is provided as attached to the second flow divider 15 to prevent the movement of the second electrode 16 in relation to the second flow divider 15.

[0149] The second electrode 16 is arranged in the opening 153 of the second flow divider 15. In other words, the second electrode 16 attached to the second flow divider 15 in such a way that the flow of electrolyte through the opening 153 of the second flow divider 15 is prevented. In other words, the second electrode 16 is sealed to the second flow divider 15. According to some embodiments, providing the second electrode 16 comprises providing the second electrode 16 in the cutout 157 of the second flow divider 15. In other words, the second electrode 16 is provided as circumferentially surrounded by the second flow divider 15.

[0150] According to some embodiments, the second electrode 16 comprises a second electrode plate 161 having a first surface 1611 and a second surface 1612 opposite the first surface 1611. Preferably, the second electrode plate 161 is a bipolar plate.

[0151] According to some embodiments, the method comprises screen printing conductive ink, such as carbon ink, on the second surface 1612 of the second electrode plate 161. The conductive ink needs to have sufficient adhesion properties to be used as an adhesive. This step can be performed before providing the second electrode 16 in the second flow divider 15, or it can be performed after providing the second electrode 16 in the second flow divider 15. The method further comprises adhering a second conductive felt 162, such as a carbon felt, to the second surface 1612 of the second electrode plate 161 with the conductive ink. This step can also be performed before providing the second electrode 16 in the second flow divider 15, or it can be performed after providing the second electrode 16 in the second flow divider 15. Adhering the second conductive felt 162 to the second electrode plate 161 reduces the system overpressure and thereby increasing its efficiency compared to relying on compression to connect the conductive felt to the electrode plate.

[0152] According to some embodiments, the method comprises screen printing a coating on the second surface 1612 of the second electrode plate 161. For example, the coating is a carbon ink coating or a catalyst material coating, such as ionic conductive catalyst material coating. The purpose of the carbon ink coating is to produce a more preferable surface geometry on the second electrode 16 for reactions, such as metal deposition. The purpose of the catalyst material coating is to accelerate reactions on the second electrode 16.

[0153] Providing first gasket

[0154] The method comprises forming a first gasket 17 by screen printing gasket material on the first surface 111 of the electrode support 11 or on the second surface 132 of the first flow divider 13. Preferably, the first gasket 17 is formed by screen printing gasket material on the first surface 111 of the electrode support 11. The first gasket 17 can be formed before providing the first electrode 12 in the electrode support 11 or after providing first electrode 12 in the electrode support 11. Using screen printing for forming the first gasket 17 allows forming the gasket in situ during the production of the cell 1. This results in near zero wastage as the gasket material is only applied to the relevant areas. For example, the gasket material is not screen printed in the locations of the flow channel 136 of the first flow divider 13.

[0155] According to some embodiments, the first gasket 17 is formed after providing the first electrode 12 in the electrode support 11, and gasket material is screen printed in such a way that the first gasket 17 overlaps with the first electrode 12. In other words, the gasket material is screen printed also on the first electrode 12. In this embodiment, the gasket material is screen printed on the first electrode 12 at most in the extent in which the first flow divider 13 overlaps with the first electrode 12. In other words, the first gasket 17 seals the first electrode 12 to the electrode support 11.

[0156] The method comprises, after forming the first gasket 17 and providing the first electrode 12 in the electrode support 11, connecting the first surface 111 of the electrode support 11 and the second surface 132 of the first flow divider 13 with the first gasket 17 to obtain a fluid-tight seal between the electrode support 11 and the first flow divider 13, and to form a first cell inner space 19 defined at least by the electrode support 11, the first electrode 12, and the first flow divider 13.

[0157] After connecting the first surface 111 of the electrode support 11 and the second surface 132 of the first flow divider 13 with the first gasket 17, and providing the membrane 14 in the first flow divider 13, the first cell inner space 19 defined by the electrode support 11, the first electrode 12, the first flow divider 13, and the membrane 14 is formed.

[0158] According to some embodiments, the first electrode 12 is provided in the electrode support 11 in such a way that the first surface 1211 of the first electrode plate 121 is facing the first cell inner space 19. This means that if the first electrode 12 is provided with the first conductive felt 122, the first conductive felt 122 is facing the first cell inner space 19. According to some embodiments, the method comprises curing the gasket material of the first gasket 17 with air or heat.

[0159] According to some embodiments, the gasket material of the first gasket 17 is ultraviolet curable resin. In these embodiments, the method comprises curing the gasket material of the first gasket 17 with ultraviolet radiation before connecting the first surface 111 of the electrode support 11 and the second surface 132 of the first flow divider 13. The characteristics of the ultraviolet curable resin can be fine-tuned by controlling the ultraviolet exposure during curing allowing tuning of the chemical properties of the resin.

[0160] Providing second gasket

[0161] The method comprises forming a second gasket 18 by screen printing gasket material on the first surface 131 of the first flow divider 13 or on the second surface 152 of the second flow divider 15. Preferably, the second gasket 18 is formed by screen printing gasket material on the first surface 131 of the first flow divider 13. The second gasket 18 can be formed before providing the membrane 14 in the first flow divider 13 or after providing the membrane 14 in the first flow divider 13. Using screen printing for forming the second gasket 18 allows forming the gasket in situ during the production of the cell 1. This results in near zero wastage as the gasket material is only applied to the relevant areas. For example, the gasket material is not screen printed in the locations of the flow channel 156 of the second flow divider 15.

[0162] According to some embodiments, the second gasket 18 is formed after providing the membrane 14 in the first flow divider 13, and gasket material is screen printed in such a way that the second gasket 18 overlaps with the membrane 14. In other words, the gasket material is screen printed also on the membrane 14. In this embodiment, the gasket material is screen printed on the membrane 14 at most in the extent in which the second flow divider 15 overlaps with the membrane 14. In other words, the second gasket 18 seals the membrane 14 to the first flow divider 13.

[0163] The method comprises, after forming the second gasket 18 and providing the membrane 14 in the first flow divider 13, connecting the first surface 131 of the first flow divider 13 and the second surface 152 of the second flow divider 15 with the second gasket 18 to obtain a fluid-tight seal between the first flow divider 13 and the second flow divider 15, and to form a second cell inner space 20 defined at least by the first flow divider 13, the membrane 15, and the second flow divider 15.

[0164] After connecting the first surface 131 of the first flow divider 13 and the second surface 152 of the second flow divider 15 with the second gasket 18, and providing the second electrode 16 in the second flow divider 15, the second cell inner space 20 defined by the first flow divider 13, the membrane 15, the second flow divider 15, and the second electrode 16.

[0165] According to some embodiments, the second electrode 16 is provided in the second flow divider 15 in such a way that the second surface 1612 of the second electrode plate 161 is facing the second cell inner space 20. This means that if the second electrode 16 is provided with the second conductive felt 162, the second conductive felt 162 is facing the second cell inner space 19.

[0166] According to some embodiments, the method comprises curing the gasket material of the second gasket 18 with air or heat.

[0167] According to some embodiments, the gasket material of the second gasket 18 is ultraviolet curable resin. In these embodiments, the method comprises curing the gasket material of the second gasket 18 with ultraviolet radiation before connecting the first surface 131 of the first flow divider 13 and the second surface 152 of the second flow divider 15. The characteristics of the ultraviolet curable resin can be finetuned by controlling the ultraviolet exposure during curing allowing tuning of the chemical properties of the resin.

[0168] The invention has been described above with reference to the examples shown in the figures. However, the invention is in no way restricted to the above examples but may vary within the scope of the claims.

Claims

CLAIMS1. An electrochemical reactor for a hybrid redox flow battery, comprising at least one cell (1); c h a r a c t e r i z e d in that the cell (1) comprises an electrode support (11) having a first surface (111) and a second surface (112) opposite the first surface (111), and arranged to support an electrode; the cell (1) comprises a first electrode (12) arranged in the electrode support CH); the cell (1) comprises a first flow divider (13) having a first surface (131) and a second surface (132) opposite the first surface (131), arranged to support a membrane, and comprising an opening (133) extending from the first surface (131) to the second surface (132), an inlet (134) for electrolyte, an outlet (135) for electrolyte, and a flow channel (136) providing a fluid connection for electrolyte between the inlet (134) and the outlet (135) via the opening (133);- the first surface (111) of the electrode support (11) is facing the second surface (132) of the first flow divider (13);- the cell (1) comprises a membrane (14) arranged in the first flow divider (13); the cell (1) comprises a second flow divider (15) having a first surface (151) and a second surface (152) opposite the first surface (151), arranged to support an electrode, and comprising an opening (153) extending from the first surface (151) to the second surface (152), an inlet (154) for electrolyte,- an outlet (155) for electrolyte, anda flow channel (156) providing a fluid connection for electrolyte between the inlet (154) and the outlet (155) via the opening (153); the first surface (131) ofthe first flow divider (13) is facing the second surface (152) of the second flow divider (15);- the cell (1) comprises a second electrode (16) arranged in the second flow divider (15); the cell (1) comprises a first gasket (17) arranged between the first surface (111) of the electrode support (11) and the second surface (132) of the first flow divider (13) for creating a fluid-tight seal between the electrode support (11) and the first flow divider (13), the first gasket (17) being screen printed; the cell (1) comprises a second gasket (18) arranged between the first surface (131) ofthe first flow divider (13) and the second surface (152) ofthe second flow divider (15) for creating a fluid-tight seal between the first flow divider (13) and the second flow divider (15), the second gasket (18) being screen printed; the electrode support (11), the first electrode (12), the first flow divider (13), and the membrane (14) define a first cell inner space (19), the first cell inner space (19) being in a fluid connection with the flow channel (136) of the first flow divider (13); the first flow divider (13), the membrane, the second flow divider (15), and the second electrode (16) define a second cell inner space (20), the second cell inner space (20) being in a fluid connection with the flow channel (156) of the second flow divider (15); and- the second cell inner space (20) is separated from the first cell inner space (19) by the membrane (14).

2. The electrochemical reactor according to claim 1, c h a r a c t e r i z e d in that the electrode support (11) comprises a cutout (117), preferably in the first surface (111), for supporting an electrode;the first electrode (12) is arranged in the cutout (117) of the electrode support CH); the first flow divider (13) comprises a cutout (137), preferably in the first surface (131), surrounding the opening (133) for supporting a membrane; the membrane (14) is arranged in the cutout (137) of the first flow divider (13); the second flow divider (15) comprises a cutout (157), preferably in the first surface (151), surrounding the opening (153) for supporting an electrode; and the second electrode (16) is arranged in the cutout (157) of the second flow divider (15).

3. The electrochemical reactor according to claim 1 or 2, characterized in that the electrode support (11) comprises an opening (113) extending from the first surface (111) to the second surface (112),- an inlet (114) for electrolyte, an outlet (115) for electrolyte, and- a flow channel (116) providing a fluid connection for electrolyte between the inlet (114) and the outlet (115) via the opening (113); wherein the cutout (117) surrounds the opening (113).

4. The electrochemical reactor according to any one of the preceding claims, characterized in that the first gasket (17) and the second gasket (18) comprise ultraviolet curable resin.

5. The electrochemical reactor according to any one of the preceding claims, characterized in that the thickness of the first gasket (17) is 20 to 200 gm; and the thickness of the second gasket (18) is 20 to 200 gm.

6. The electrochemical reactor according to any one of the preceding claims, c h a r a c t e r i z e d in that the first electrode (12) comprises a first electrode plate (121) having a first surface (1211) and a second surface (1212) opposite the first surface (1211); the first surface (1211) of the first electrode plate (121) is facing the first cell inner space (19); the first electrode (12) comprises a first conductive felt (122), such as a carbon felt, adhered to the first surface (1211) of the first electrode plate (121) using screen printed conductive ink, such as carbon ink; the second electrode (16) comprises a second electrode plate (161) having a first surface (1611) and a second surface (1612) opposite the first surface (1611); the second surface (1612) of the second electrode plate (161) is facing the second cell inner space (20); and the second electrode (16) comprises a second conductive felt (162), such as a carbon felt, adhered to the second surface (1612) of the second electrode plate (161) using screen printed conductive ink, such as carbon ink.

7. The electrochemical reactor according to any one of the preceding claims, c h a r a c t e r i z e d in that the first electrode (12) comprises a first electrode plate (121) having a first surface (1211) and a second surface (1212) opposite the first surface (1211); the first surface (1211) of the first electrode plate (121) is facing the first cell inner space (19); the first electrode (12) comprises a screen printed coating, such as a carbon ink coating or a catalyst material coating, provided on the first surface (1211) of the first electrode plate (121);the second electrode (16) comprises a second electrode plate (161) having a first surface (1611) and a second surface (1612) opposite the first surface (1611); the second surface (1612) of the second electrode plate (161) is facing the second cell inner space (20); and the second electrode (16) comprises a screen printed coating, such as a carbon ink coating or a catalyst material coating, provided on the second surface (1612) of the second electrode plate (161).

8. The electrochemical reactor according to any one of the preceding claims, characterized in that the membrane (14) comprises a porous support sheet (141) and a screen printed ion exchange membrane layer (142) provided on a surface of the porous support sheet (141).

9. The electrochemical reactor according to any one of the preceding claims, characterized in that the cell (1) comprises a turbulence promoter (21) connected to the membrane (14).

10. A method for producing an electrochemical reactor for a hybrid redox flow battery, characterized in that the method comprises- providing an electrode support (11) having a first surface (111) and a second surface (112) opposite the first surface (111), and arranged to support an electrode; providing a first electrode (12) in the electrode support (11); providing a first flow divider (13) having a first surface (131) and a second surface (132) opposite the first surface (131), arranged to support a membrane, and comprising an opening (133) extending from the first surface to the second surface, an inlet (134) for electrolyte, an outlet (135) for electrolyte, anda flow channel (136) providing a fluid connection for electrolyte between the inlet (134) and the outlet (135) via the opening (133); providing a membrane (14) in the first flow divider (13); providing a second flow divider (15) having a first surface (151) and a second surface (152) opposite the first surface (151), arranged to support an electrode, and comprising an opening (133) extending from the first surface to the second surface, an inlet (134) for electrolyte, an outlet (135) for electrolyte, and a flow channel (136) providing a fluid connection for electrolyte between the inlet (134) and the outlet (135) via the opening (133); providing a second electrode (16) in the second flow divider (15); forming a first gasket (17) by screen printing gasket material on the first surface (111) of the electrode support (11) or on the second surface (132) of the first flow divider (13); after forming the first gasket (17) and providing the first electrode (12) in the electrode support (11), connecting the first surface (111) of the electrode support (11) and the second surface (132) of the first flow divider (13) with the first gasket (17) to obtain a fluid-tight seal between the electrode support (11) and the first flow divider (13), and to form a first cell inner space (19) defined at least by the electrode support (11), the first electrode (12), and the first flow divider (13); forming a second gasket (18) by screen printing gasket material on the first surface (131) of the first flow divider (13) or on the second surface (152) of the second flow divider (15); and after forming the second gasket (18), connecting the first surface (131) of the first flow divider (13) and the second surface (152) of the second flow divider (15) with the second gasket (18) to obtain a fluid-tight seal between the first flow divider (13) and the second flow divider (15), and to form a second cellinner space (20) defined at least by the first flow divider (13), the membrane (14), and the second flow divider (15).

11. The method according to claim 10, c h a r a c t e r i z e d in that the electrode support (11) comprises a cutout (117), preferably in the first surface (111), for supporting an electrode; providing the first electrode (12) comprises providing the first electrode (12) in the cutout (117) of the electrode support (11); the first flow divider (13) comprises a cutout (137) surrounding the opening (133) for supporting a membrane; providing the membrane (14) comprises providing the membrane (14) in the cutout (137) of the first flow divider (13); the second flow divider (15) comprises a cutout (157) surrounding the opening (153) for supporting an electrode; and providing the second electrode (16) comprises providing the second electrode (16) in the cutout (157) of the second flow divider (15).

12. The method according to claim 10 or 11, c h a r a c t e r i z e d in that the electrode support (11) comprises- an opening (113) extending from the first surface (111) to the second surface (112), an inlet (114) for electrolyte, an outlet (115) for electrolyte, and a flow channel (116) providing a fluid connection for electrolyte between the inlet (114) and the outlet (115) via the opening (113); wherein the cutout (117) surrounds the opening (113).

13. The method according to any one of claims 10 to 12, c h a r a c t e r i z e d in that the gasket material of the first gasket (17) and the second gasket (18) is ultraviolet curable resin; and the method comprises curing the gasket material of the first gasket (17) with ultraviolet radiation before connecting the first surface (111) of the electrode support (11) and the second surface (132) of the first flow divider (13), and curing the gasket material of the second gasket (18) with ultraviolet radiation before connecting the first surface (131) of the first flow divider (13) and the second surface (152) of the second flow divider (15).

14. The method according to any one of claims 10 to 13, c h a r a c t e r i z e d in that the first electrode (12) comprises a first electrode plate (121) having a first surface (1211) and a second surface (1212) opposite the first surface (1211); the first electrode (12) is provided in the electrode support (11) in such a way that the first surface (1211) of the first electrode plate (121) is facing the first cell inner space (19); the second electrode (16) comprises a second electrode plate (161) having a first surface (1611) and a second surface (1612) opposite the first surface (1611); the second electrode (16) is provided in the second flow divider (15) in such a way that the second surface (1612) of the second electrode plate (161) is facing the second cell inner space (20); and the method comprises screen printing conductive ink, such as carbon ink, on the first surface (1211) of the first electrode plate (121),adhering a first conductive felt (122), such as a carbon felt, to the first surface (1211) of the first electrode plate (121) with the conductive ink, screen printing conductive ink, such as carbon ink, on the second surface (1612) of the second electrode plate (161), and- adhering a second conductive felt (162), such as a carbon felt, to the second surface (1612) of the second electrode plate (161) with the conductive ink.

15. The method according to any one of claims 10 to 14, c h a r a c t e r i z e d in that the first electrode (12) comprises a first electrode plate (121) having a first surface (1211) and a second surface (1212) opposite the first surface (1211); the first electrode (12) is provided in the electrode support (11) in such a way that the first surface (1211) of the first electrode plate (121) is facing the first cell inner space (19); the second electrode (16) comprises a second electrode plate (161) having a first surface (1611) and a second surface (1612) opposite the first surface (1611); the second electrode (16) is provided in the second flow divider (15) in such a way that the second surface (1612) of the second electrode plate (161) is facing the second cell inner space (20); and the method comprises screen printing a coating, such as a carbon ink coating or a catalyst material coating, on the first surface (1211) of the first electrode plate (121), and- screen printing a coating, such as a carbon ink coating or a catalyst material coating, on the second surface (1612) of the second electrode plate (161).

16. The method according to any one of claims 10 to 15, c h a r a c t e r i z e d in that providing the membrane (14) comprises providing a porous support sheet (141), screen printing ion exchange polymer dissolved in a solvent on the porous support sheet (141), and allowing the solvent to evaporate to form an ion exchange membrane layer (142) on the porous support sheet (141).

17. The method according to any one of claims 10 to 16, c h a r a c t e r i z e d in that the method comprises providing a turbulence promoter (21) in connection with the membrane (14).

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