Electrolytic bath

Abstract

The utility model discloses an electrolytic bath, which relates to the field of electrolytic hydrogen production and is used for solving the problem of poor flow field uniformity of a large electrolytic bath. The electrolytic bath comprises two end pressing plates arranged in the first direction and a plurality of polar plate assemblies, and the polar plate assembly located in the middle is a middle bipolar polar plate assembly; the middle bipolar polar plate assembly comprises a middle polar plate frame and two flat plates, and an electrolyte cavity is defined by the middle polar plate frame and the two flat plates; the middle polar plate frame is provided with an electrolyte inlet, a plurality of electrolyte anode distribution runners and a plurality of electrolyte cathode distribution runners; two ends of the electrolyte inlet are respectively communicated with the electrolyte cavity and an external electrolyte pipeline; inlets of the electrolyte anode distribution flow channel and the electrolyte cathode distribution flow channel are communicated with the electrolyte cavity, an outlet of the electrolyte anode distribution flow channel is communicated with the anode small chamber, and an outlet of the electrolyte cathode distribution flow channel is communicated with the cathode small chamber; and the electrolyte anode distribution flow channels and the electrolyte cathode distribution flow channels are alternately arranged along the circumferential direction of the middle polar plate frame.

Description

Technical Field

[0001] The utility model relates to the technical field of electrolytic hydrogen production, in particular to an electrolytic cell. Background Art

[0002] Hydrogen production by water electrolysis is an important method for preparing hydrogen in industry. In a water electrolyzer, the chemical reaction of water electrolysis is completed in the electrolysis chamber. The electrolysis chamber is the most basic unit of the electrolyzer. Multiple electrolysis chambers are compressed between two end pressure plates by multiple tensioning screws. With the emergence of market demand for high-level hydrogen production, large-scale alkaline electrolyzers will become the first choice for the rapid development of water electrolysis hydrogen production in the future. In the process of alkaline water electrolyzers developing in the direction of large-scale, the length of the electrolyzer will increase, the electrolysis area will also increase, the flow path of the electrolyte in the tank will become longer, and the uniformity of the flow will also deteriorate, which will cause the uniformity of the flow field and thermal field inside the electrolyzer to deteriorate, and affect the energy consumption and uniformity of the electrolysis reaction. Utility Model Content

[0003] The utility model aims to provide an electrolytic cell to improve the uniformity of the flow field in the electrolytic cell.

[0004] In a first aspect, the utility model provides an electrolytic cell, comprising two end pressure plates arranged along a first direction and a plurality of plate assemblies located between the two end pressure plates, wherein at least one of the plurality of plate assemblies is an intermediate bipolar plate assembly; two adjacent plate assemblies are sealed to form an anode chamber and a cathode chamber, and the anode chambers and cathode chambers in the electrolytic cell are arranged alternately;

[0005] The intermediate bipolar plate assembly comprises an intermediate plate frame and two flat plates, the two flat plates are parallel to each other and fixed on the edge of the intermediate plate frame at intervals, and the intermediate plate frame and the two flat plates enclose an electrolyte cavity;

[0006] The intermediate electrode plate frame is provided with an electrolyte inlet, at least two electrolyte anode distribution channels and at least two electrolyte cathode distribution channels. The electrolyte inlet is arranged on the periphery of the intermediate electrode plate frame and is connected to the electrolyte cavity; the inlets of the electrolyte anode distribution channel and the electrolyte cathode distribution channel are both connected to the electrolyte cavity, the outlet of the electrolyte anode distribution channel is connected to the anode chamber, and the outlet of the electrolyte cathode distribution channel is connected to the cathode chamber; the electrolyte anode distribution channel and the electrolyte cathode distribution channel are alternately arranged along the circumference of the intermediate electrode plate frame.

[0007] When the above technical solution is adopted, since the electrolyte inlet is arranged on the intermediate plate frame of at least one intermediate bipolar plate assembly of the electrolytic cell, the electrolyte enters the electrolyte cavity in the intermediate plate frame from at least one position in the middle of the electrolytic cell. After that, the electrolyte is distributed to both sides from the electrolyte anode distribution channel and the electrolyte cathode distribution channel and enters the anode chamber and the cathode chamber respectively, thereby narrowing the distribution path of the electrolyte and realizing rapid distribution of the electrolyte. When there are at least two electrolyte anode distribution channels and electrolyte cathode distribution channels, since the electrolyte anode distribution channels and the electrolyte cathode distribution channels are alternately arranged along the circumference of the intermediate plate frame, the electrolyte can be diffused into each anode chamber and each cathode chamber at multiple points within a larger central angle range of each plate assembly, so that the distribution flow field of the electrolyte in the anode chamber and the cathode chamber can be more uniform, thereby improving the uniformity of the electrolysis reaction and reducing the energy consumption of the electrolytic cell.

[0008] In some possible implementations, the number of electrolyte inlets is at least two, at least one electrolyte inlet is located in the middle of the intermediate plate frame in the vertical direction, and the remaining electrolyte inlets are located in the upper and / or lower part of the intermediate plate frame. In this arrangement, when the electrolyte inlet is located in the middle and upper part of the intermediate plate frame, the electrolyte enters the electrolyte cavity from the middle and upper part of the intermediate plate frame, which can take away part of the heat in the area and promote a more uniform temperature of the intermediate plate frame and the surrounding electrolytic chambers. When the electrolyte inlet is located in the middle and lower part of the intermediate plate frame, the electrolyte inlet can be staggered a certain distance from the gas outlet at the top of the intermediate plate frame to facilitate the arrangement of the pipeline.

[0009] In some possible implementations, the electrolyte inlet penetrates the intermediate electrode plate frame in the radial direction of the intermediate electrode plate frame.

[0010] In some possible implementations, the electrolyte anode distribution channel and the electrolyte cathode distribution channel both include a radial section and an axial section, the radial section extends along the radial direction of the intermediate plate frame, the axial section extends along the axial direction of the intermediate plate frame and penetrates the two end surfaces of the intermediate plate frame, the two ends of the radial section are respectively connected to the electrolyte cavity and the axial section, the axial section of the electrolyte anode distribution channel is connected to the anode chamber, and the axial section of the electrolyte cathode distribution channel is connected to the cathode chamber. In this arrangement, the electrolyte in the electrolyte cavity enters each electrolyte anode distribution channel and electrolyte cathode distribution channel from the radial section, and then is distributed to the anode chamber and cathode chamber between each plate assembly on both sides of the intermediate plate frame through the axial section. The electrolyte anode distribution channel and the electrolyte cathode distribution channel have a simple structure and are easy to process and manufacture.

[0011] In some possible implementations, the cross-section of the axial segment perpendicular to the axial direction of the intermediate plate frame is circular, elliptical, waist-shaped or polygonal; the cross-section of the radial segment is circular, elliptical or polygonal.

[0012] In some possible implementations, at least one electrolyte anode distribution channel and at least one electrolyte cathode distribution channel are located at the lower part of the intermediate plate frame. This arrangement allows the electrolyte entering from the electrolyte inlet to be continuously distributed to the lower areas of each anode chamber and cathode chamber, and the electrolyte gradually flows from the lower part to the upper part, during which an electrolytic reaction is performed.

[0013] In some possible implementations, the center angle between two of the at least two electrolyte anode distribution channels located at both ends is 60° to 180°, and / or the center angle between two of the at least two electrolyte cathode distribution channels located at both ends is 60° to 180°. This arrangement expands the diffusion range of the electrolyte in the anode chamber and the cathode chamber, and improves the uniformity of distribution.

[0014] In some possible implementations, a hydrogen collection channel and an oxygen collection channel are provided on the upper portion of the intermediate plate frame, the hydrogen collection channel is connected to the cathode chamber, and the oxygen collection channel is connected to the anode chamber. In this arrangement, the oxygen and hydrogen generated by electrolysis are collected by the intermediate plate frame located in the middle of the electrolytic cell, shortening the gas transport path and reducing the gas output resistance.

[0015] In some possible implementations, there is at least one hydrogen collection channel and at least one oxygen collection channel, and the hydrogen collection channel and the oxygen collection channel are respectively located on both sides of the vertical diameter cross section of the intermediate plate frame. This arrangement facilitates the arrangement of external pipelines respectively connected to the hydrogen collection channel and the oxygen collection channel.

[0016] In some possible implementations, the hydrogen collection channel and the oxygen collection channel both include a second radial section and a second axial section, the second radial section penetrates the outer peripheral surface of the intermediate plate frame along the radial direction of the intermediate plate frame, the second axial section extends along the axial direction of the intermediate plate frame and penetrates the two end surfaces of the intermediate plate frame, the second radial section is connected to the second axial section, the second axial section of the oxygen collection channel is connected to the anode chamber, and the second axial section of the hydrogen collection channel is connected to the cathode chamber. With such an arrangement, the structures of the hydrogen collection channel and the oxygen collection channel are simple and easy to manufacture.

[0017] In some possible implementations, the outlet ends of the hydrogen collecting channel and the oxygen collecting channel and the inlet end of the electrolyte inlet are flush with the outer peripheral surface of the intermediate plate frame; in this way, the structure of the intermediate plate frame is simple and easy to process.

[0018] Alternatively, flange surfaces are formed on the outer peripheral surface of the intermediate plate frame at positions corresponding to the outlet ends of the hydrogen collecting channel and the oxygen collecting channel and the inlet end of the electrolyte inlet; in this way, the fluid inlet and outlet are directly connected to the external pipeline through the flange surface on the intermediate plate frame, eliminating welding, avoiding the stress formed by welding, reducing stress corrosion, and reducing the risk of leakage at the connection between the intermediate plate frame and the external pipeline.

[0019] Alternatively, the outlet ends of the hydrogen collecting flow channel and the oxygen collecting flow channel and the inlet end of the electrolyte inlet are all connected with connecting pipes, and one end of the connecting pipe away from the intermediate plate frame is a flange structure.

[0020] In some possible implementations, the remaining plate assemblies located on both sides of the middle bipolar plate assembly in the plurality of plate assemblies include at least two bipolar plate assemblies;

[0021] The bipolar plate assembly includes a bipolar plate and a plate frame. The plate frame is arranged on the periphery of the bipolar plate. The two sides of the bipolar plate are respectively an anode side and a cathode side. The anode side is opposite to the anode chamber, and the cathode side is opposite to the cathode chamber.

[0022] At least one anode flow channel, at least one cathode flow channel, a hydrogen outlet flow channel and an oxygen outlet flow channel are arranged in the electrode plate frame. The anode flow channel and the cathode flow channel are alternately arranged along the circumference of the electrode plate frame, and the anode flow channel is connected to the electrolyte anode distribution flow channel in a one-to-one correspondence, the cathode flow channel is connected to the electrolyte cathode distribution flow channel in a one-to-one correspondence, the anode flow channel and the oxygen outlet flow channel are both connected to the anode chamber, and the cathode flow channel and the hydrogen outlet flow channel are both connected to the cathode chamber.

[0023] When the above technical solution is adopted, the electrolyte flows from the electrolyte cavity of the intermediate plate frame, and a part of the electrolyte flows to the anode flow channel of each bipolar plate through the electrolyte anode distribution channel, and then enters each anode chamber through the anode flow channel. Oxygen is generated after electrolysis, and the oxygen enters the oxygen outlet flow channel with the electrolyte, and finally gathers into the oxygen collection flow channel of the intermediate plate frame, and is discharged to the external oxygen pipeline. Another part of the electrolyte flows to the cathode flow channel of each bipolar plate through the electrolyte cathode distribution channel, and then enters each cathode chamber through the cathode flow channel. Hydrogen is generated after electrolysis, and the hydrogen enters the hydrogen outlet flow channel with the electrolyte, and finally gathers into the hydrogen collection flow channel of the intermediate plate frame, and is discharged to the external hydrogen pipeline. The entire electrolyte distribution flow channel and gas collection flow channel shorten the electrolyte and gas flow path, improve the distribution uniformity, and the electrolytic cell structure is compact.

[0024] In some possible implementations, a diaphragm is further provided between two adjacent electrode plate assemblies, and the diaphragm is used to separate the anode chamber from the cathode chamber;

[0025] The cathode chamber is composed of the cathode surface of the plate assembly, the support net and the cathode electrode net, and the anode chamber is composed of the anode surface of the plate assembly, the support net and the anode electrode net;

[0026] Or, the cathode chamber is composed of the cathode surface of the electrode assembly and the cathode electrode mesh, and the anode chamber is composed of the anode surface of the electrode assembly and the anode electrode mesh, and the cathode surface and the anode surface have convex parts, and the convex parts are used to support the cathode electrode mesh and the anode electrode mesh;

[0027] In some possible implementations, the thickness of the bipolar plate is 7 mm to 10 mm, which can further reduce the weight of the electrolytic cell and reduce costs.

[0028] In some possible implementations, a sealing gasket is further provided between two adjacent plate assemblies, the sealing gasket being located between one end of the plate assembly and the diaphragm, and a hole is provided on the end face of the plate frame of the plate assembly to release the compression of the sealing gasket. With such a configuration, the sealing gasket can be partially embedded in the hole after compression to form a limit position, thereby preventing the sealing gasket from being squeezed out of the electrolytic cell after compression, thereby affecting the sealing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0030] Figure 1 A schematic diagram of the internal structure of an electrolytic cell provided in an embodiment of the utility model;

[0031] Figure 2 A schematic diagram of fluid flow in an electrolytic cell provided in an embodiment of the utility model;

[0032] Figure 3 A schematic diagram of the structure of an electrolytic cell provided in an embodiment of the utility model;

[0033] Figure 4 A schematic diagram of the structure of an intermediate plate frame provided in an embodiment of the utility model;

[0034] Figure 5 for Figure 4 A schematic diagram of a front view of an intermediate plate frame;

[0035] Figure 6 A side cross-sectional schematic diagram of an intermediate plate assembly provided in an embodiment of the utility model;

[0036] Figure 7 A schematic diagram of the structure of another intermediate plate frame provided in an embodiment of the utility model;

[0037] Figure 8 for Figure 7 A schematic diagram of a front view of an intermediate plate frame;

[0038] Fig. 9 A schematic structural diagram of another intermediate plate frame provided in an embodiment of the utility model;

[0039] Fig.10 for Fig. 9 A schematic diagram of a front view of an intermediate plate frame;

[0040] Fig.11 A schematic structural diagram of a bipolar plate frame provided in an embodiment of the utility model.

[0041] Reference numerals: 1 is an intermediate bipolar plate assembly, 101 is an oxygen collecting channel, 1011 is an oxygen guide groove, 102 is a hydrogen collecting channel, 103 is an electrolyte inlet, 104 is an electrolyte anode distribution channel, 1041 is an anode guide groove, 105 is an electrolyte cathode distribution channel, 1051 is a cathode guide groove, 106 is an oxygen outlet, 107 is a hydrogen outlet, 108 is a mounting hole, 109 is a flange surface, 11 0 is an avoidance gap, 111 is a flat plate, 112 is an electrolyte cavity, 2 is an end pressure plate, 3 is a plate assembly, 301 is an oxygen outlet flow channel, 3011 is an oxygen through slot, 302 is a hydrogen outlet flow channel, 3021 is a hydrogen through slot, 303 is an anode flow channel, 3031 is an anode chamber through slot, 304 is a cathode flow channel, 3041 is a cathode chamber through slot, 4 is a tightening bolt, 5 is an oxygen pipeline, 6 is a hydrogen pipeline, and 7 is an electrolyte pipeline. DETAILED DESCRIPTION

[0042] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0043] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0044] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0045] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0046] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0047] See also Figure 1-Figure 5 An embodiment of the utility model provides an electrolytic cell, which includes two end pressure plates 2 arranged along a first direction and a plurality of electrode plate assemblies 3 located between the two end pressure plates 2. A tightening force is applied to the two end pressure plates 2 by tightening bolts 4, so that the plurality of electrode plate assemblies 3 located between the two end pressure plates 2 are pressed and sealed against each other. Among them, at least one of the multiple electrode assemblies 3 is an intermediate bipolar plate assembly 1, which can be one, two, three or more, and two adjacent intermediate bipolar plate assemblies 1 are arranged at intervals; the two electrode assemblies 3 adjacent to the two end pressure plates 2 are single-pole plate assemblies, and the single-pole plate of the single-pole plate assembly has only one electrode; the remaining electrode assemblies 3 located between the single-pole plate assembly and the intermediate bipolar plate assembly 1 and the electrode assemblies 3 located between two adjacent intermediate bipolar plate assemblies 1 are bipolar plate assemblies; the two adjacent electrode plate assemblies 3 are sealed to form an anode chamber and a cathode chamber, wherein one side of the bipolar plate assembly is opposite to the anode chamber, and the other side is opposite to the cathode chamber, the two sides of the intermediate bipolar plate assembly 1 correspond to the anode chamber and the cathode chamber respectively, and one side of the single-pole plate assembly corresponds to the anode chamber or the cathode chamber; the anode chamber and the cathode chamber in the electrolytic cell are arranged alternately.

[0048] The intermediate bipolar plate assembly 1 includes an intermediate plate frame and two flat plates 111. Figure 4-Figure 9 As shown, the intermediate plate frame is a ring frame structure, two flat plates 111 are parallel to each other and fixed on the edge of the intermediate plate frame at intervals, the intermediate plate frame and the two flat plates 111 surround an electrolyte cavity 112, the two flat plates 111 are respectively used as two electrode plates, one side of one flat plate 111 facing away from the electrolyte cavity 112 corresponds to an anode chamber, and the other side of the flat plate 111 facing away from the electrolyte cavity 112 corresponds to a cathode chamber;

[0049] The intermediate plate frame is provided with an electrolyte inlet 103, at least one electrolyte anode distribution channel 104 and at least one electrolyte cathode distribution channel 105. The electrolyte inlet 103 is arranged on the periphery of the intermediate plate frame, and the two ends of the electrolyte inlet 103 are respectively connected to the electrolyte cavity 112 and the external electrolyte pipeline 7; the inlets of the electrolyte anode distribution channel 104 and the electrolyte cathode distribution channel 105 are both connected to the electrolyte cavity 112, the outlet of the electrolyte anode distribution channel 104 is connected to the anode chamber, and the outlet of the electrolyte cathode distribution channel 105 is connected to the cathode chamber; the electrolyte anode distribution channel 104 and the electrolyte cathode distribution channel 105 are alternately arranged along the circumference of the intermediate plate frame, that is, when When there are at least two electrolyte anode distribution channels 104 and electrolyte cathode distribution channels 105, there is one electrolyte cathode distribution channel 105 between every two electrolyte anode distribution channels 104, and there is one electrolyte anode distribution channel 104 between every two electrolyte cathode distribution channels 105. The number of electrolyte anode distribution channels 104 can be one, two, three, four, five or more, and the number of electrolyte cathode distribution channels 105 can be one, two, three, four, five or more. The number of electrolyte anode distribution channels 104 and the number of electrolyte cathode distribution channels 105 can be the same or differ by one, and there is one more distribution channel of the same type located at both ends. The electrolyte anode distribution channel 104 is connected to the anode chamber via an anode liquid guide groove 1041 provided on one end face of the corresponding anode chamber of the intermediate plate frame, and the electrolyte cathode distribution channel 105 is connected to the cathode chamber via a cathode liquid guide groove 1051 provided on one end face of the corresponding cathode chamber of the intermediate plate frame.

[0050] When working, see Figure 2 As shown by the flow arrows of the electrolyte in the electrolyte (shown by the solid line), the electrolyte transported in the electrolyte pipeline 7 enters the electrolyte cavity 112 in the intermediate plate frame through the electrolyte inlet 103 on at least one intermediate bipolar plate assembly 1 of the electrolytic cell, and then the electrolyte is distributed to both sides from the electrolyte anode distribution channel 104 and the electrolyte cathode distribution channel 105 and enters the anode chamber and the cathode chamber respectively for electrolysis.

[0051] As can be seen from the above, the electrolyte enters the electrolytic cell from at least one position between the end pressure plates through at least one intermediate bipolar plate assembly, and the electrolyte distribution path is shortened. When an intermediate bipolar plate assembly is located in the middle position of the electrolytic cell, the electrolyte distribution path can be reduced to half the length of the electrolytic cell, which can achieve rapid distribution of the electrolyte. When there are at least two electrolyte anode distribution channels and electrolyte cathode distribution channels, the electrolyte anode distribution channel 104 and the electrolyte cathode distribution channel 105 are arranged along the intermediate plate frame. The circumferential alternating arrangement can make the electrolyte diffuse into each anode chamber and each cathode chamber at multiple points within a larger central angle range of each electrode assembly 3, and can make the distribution flow field of the electrolyte in the anode chamber and the cathode chamber more uniform, thereby improving the uniformity of the electrolysis reaction and reducing the energy consumption of electrolysis. In addition, the electrolyte enters each anode chamber and cathode chamber in a multi-point and large-scale manner, which can make the thermal field distribution in the electrolysis chamber more uniform, and the flow field and thermal field of adjacent anode chambers and cathode chambers are basically symmetrical relative to the diaphragm, thereby improving the electrolysis efficiency.

[0052] like Figure 1 , Figure 3-Figure 8 As shown, in some embodiments, the number of electrolyte inlets 103 is at least two, at least one electrolyte inlet 103 is located in the middle of the intermediate electrode plate frame in the vertical direction, and the remaining electrolyte inlets 103 are located in the upper and / or lower part of the intermediate electrode plate frame.

[0053] Exemplarily, there may be four electrolyte inlets 103, two of which are located at both ends of the horizontal diameter direction of the intermediate plate frame, and the other two are located at the lower position or the upper position of the two ends of the horizontal diameter direction. Of course, the number of electrolyte inlets 103 can also be one, two, three or more. In this way, when the electrolyte inlet 103 is located in the middle and upper part of the intermediate plate frame, the electrolyte enters the electrolyte cavity 112 from the middle and upper part of the intermediate plate frame, which can take away part of the heat in the area and promote the temperature of the intermediate plate frame and the surrounding electrolytic chamber to be more uniform. When the electrolyte inlet 103 is located in the middle and lower part of the intermediate plate frame, the electrolyte inlet 103 can be staggered a certain distance from the gas outlet at the top of the intermediate plate frame to facilitate the arrangement of external pipelines.

[0054] Furthermore, in some embodiments, the electrolyte inlet 103 penetrates the intermediate electrode plate frame in the radial direction of the intermediate electrode plate frame to facilitate the positioning and processing of the electrolyte inlet 103. Of course, the electrolyte inlet 103 can also penetrate the intermediate electrode plate frame at an angle to the radial direction of the intermediate electrode plate frame.

[0055] like Figure 1 , Figure 4-Figure 8As shown, the electrolyte anode distribution channel 104 and the electrolyte cathode distribution channel 105 both include a radial section and an axial section, the radial section extends along the radial direction of the intermediate plate frame, and the axial section extends along the axial direction of the intermediate plate frame and penetrates the two end surfaces of the intermediate plate frame to form a T-shaped channel structure, and the two ends of the radial section are respectively connected to the electrolyte cavity 112 and the axial section, the axial section of the electrolyte anode distribution channel 104 is connected to the anode chamber, and the axial section of the electrolyte cathode distribution channel 105 is connected to the cathode chamber. Specifically, the axial section of the electrolyte anode distribution channel 104 is connected to the anode chamber through the anode liquid guide groove 1041, and the axial section of the electrolyte cathode distribution channel 105 is connected to the cathode chamber through the cathode liquid guide groove 1051. With such arrangement, the electrolyte in the electrolyte cavity 112 enters each electrolyte anode distribution channel 104 and electrolyte cathode distribution channel 105 through the radial section, and then is distributed to the anode chamber and cathode chamber between each electrode assembly 3 on both sides of the intermediate electrode frame through the axial section. The electrolyte anode distribution channel 104 and electrolyte cathode distribution channel 105 have a simple structure and can be processed through once along the axial direction, which is convenient for processing and manufacturing.

[0056] Exemplarily, the cross-sectional shape of the axial section perpendicular to the axial direction of the intermediate plate frame is circular, elliptical, waist-shaped or polygonal, and the polygon may be specifically a triangle, square, etc.; the cross-sectional shape of the radial section is circular, elliptical or polygonal, and the polygon may be specifically a triangle, direction, etc. Of course, the electrolyte anode distribution channel 104 and the electrolyte cathode distribution channel 105 may also have other structural forms, not limited to the forms listed in this embodiment, as long as the electrolyte can be distributed from the electrolyte cavity 112 to the electrolysis chambers on both sides.

[0057] like Figure 1 , Figure 2 , Figure 4-Figure 8 As shown, at least one electrolyte anode distribution channel 104 and at least one electrolyte cathode distribution channel 105 are located at the lower part of the intermediate plate frame. That is, they are located at the lower half of the intermediate plate frame. Such arrangement enables the electrolyte entering from the electrolyte inlet 103 to be continuously distributed to the lower area of ​​each anode chamber and cathode chamber, and the electrolyte gradually flows from the lower part to the upper part. During this process, an electrolytic reaction is performed.

[0058] For example, the central angle between two of the at least two electrolyte anode distribution channels 104 located at both ends can be 60° to 180°. Similarly, the central angle between two of the at least two electrolyte cathode distribution channels 105 located at both ends can be 60° to 180°, so as to expand the diffusion range of the electrolyte in the anode chamber and the cathode chamber and improve the uniformity of distribution.

[0059] like Figure 1-Figure 8As shown, in some embodiments, a hydrogen collection channel 102 and an oxygen collection channel 101 are provided on the upper part of the intermediate plate frame, the hydrogen collection channel 102 is connected to the cathode chamber, the oxygen collection channel 101 is connected to the anode chamber, the outlet of the hydrogen collection channel 102 is a hydrogen outlet 107, and the outlet of the oxygen collection channel 101 is an oxygen outlet 106. In this way, the oxygen and hydrogen generated by electrolysis are collected by the intermediate plate frame located in the middle of the electrolytic cell, which shortens the gas transportation path and reduces the gas output resistance.

[0060] For example, there are at least one hydrogen collection channel 102 and oxygen collection channel 101, specifically one, two, three, four or more, the number of hydrogen collection channel 102 and oxygen collection channel 101 can be the same or different, and the hydrogen collection channel 102 and oxygen collection channel 101 are respectively located on both sides of the vertical diameter section of the intermediate plate frame, and the vertical diameter section passes through the axis of the intermediate plate frame. Such an arrangement facilitates the separate arrangement of the hydrogen pipeline 6 connected to the hydrogen collection channel 102 and the oxygen pipeline 5 connected to the oxygen collection channel 101, and there will be no interlaced interference of the pipelines.

[0061] Further, in the present embodiment, the hydrogen collection channel 102 and the oxygen collection channel 101 both include a second radial section and a second axial section, the second radial section penetrates the outer peripheral surface of the intermediate electrode plate frame in the radial direction of the intermediate electrode plate frame, the second axial section extends along the axial direction of the intermediate electrode plate frame to penetrate the two end surfaces of the intermediate electrode plate frame, and the second radial section is connected to the second axial section; the second axial section of the oxygen collection channel 101 is connected to the anode chamber, specifically, the second axial section of the oxygen collection channel 101 is connected to the anode chamber through the oxygen guide groove 1011 provided on one end surface of the intermediate electrode plate frame close to the anode chamber; the second axial section of the hydrogen collection channel 102 is connected to the cathode chamber, specifically, the second axial section of the hydrogen collection channel 102 is connected to the cathode chamber through the hydrogen guide groove (not shown in the figure, connected to the cathode chamber) provided on one end surface of the intermediate electrode plate frame close to the cathode chamber. Figure 3 The oxygen flow channel 1011 in the cathode chamber is arranged opposite to each other) and is connected to the cathode chamber. In this way, the hydrogen collection channel 102 and the oxygen collection channel 101 are T-shaped channel structures, which are simple in structure and can be axially penetrated in one processing, which is convenient for manufacturing.

[0062] For example, the cross-sectional shape of the second axial section perpendicular to the axial direction of the intermediate plate frame is circular, elliptical, waist-shaped or polygonal, and the polygon can be specifically a triangle, square, etc.; the cross-sectional shape of the second radial section is circular, elliptical or polygonal, and the polygon can be specifically a triangle, direction, etc. Of course, the oxygen collection channel 101 and the hydrogen collection channel 102 can also have other structural forms, not limited to the forms listed in this embodiment, as long as it can realize the collection and export of gas and liquid in the anode chamber and the cathode chamber respectively.

[0063] like Figure 8 and Fig. 9 As shown, in this embodiment, the outlet ends of the hydrogen collecting channel 102 and the oxygen collecting channel 101 and the inlet end of the electrolyte inlet 103 are flush with the outer peripheral surface of the intermediate plate frame, that is, they are all arc surfaces. In this way, the structure of the intermediate plate frame is simple and easy to process.

[0064] like Figure 4 and Figure 5 As shown, in another embodiment, the outer peripheral surface of the intermediate plate frame corresponding to the outlet end of the hydrogen collecting channel 102 and the oxygen collecting channel 101 and the inlet end of the electrolyte inlet 103 are formed with flange surfaces 109, and the flange surface 109 is provided with mounting holes 108 around the inlet end or the outlet end to form a flange structure. In this way, the electrolyte inlet 103, the hydrogen outlet 107 and the oxygen outlet 106 are directly connected to the external pipeline through the flange surface 109 on the intermediate plate frame, eliminating welding, avoiding stress formed by welding, reducing stress corrosion, and reducing the risk of leakage at the connection between the intermediate plate frame and the external pipeline.

[0065] Furthermore, if Figure 4 and Figure 5 As shown, the outer surface of the intermediate plate frame is provided with a plurality of avoidance notches 110 arranged at intervals along the circumferential direction, and the extension direction of the avoidance notches 110 is parallel to the axis of the intermediate plate frame, and the avoidance notches 110 are used to accommodate the tension bolts 4 of the avoidance electrolyzer. Among them, the cross section of the avoidance notch 110 can be an arc notch, a rectangular notch or a trapezoidal notch, as long as it can accommodate the avoidance tension bolts 4. The number of the avoidance notches 110 is the same as the number of the tension bolts 4 and the arrangement positions on the circumference correspond one to one. Since it is necessary to radially open the mounting hole 108 on the intermediate plate frame, in order to make the mounting hole 108 have an effective connection depth, and to prevent the mounting hole 108 from penetrating the flow channel in the intermediate plate frame, such as the hydrogen collection flow channel 102, the oxygen collection flow channel 101, etc., therefore, the intermediate plate frame needs to increase the radial thickness, and the outer diameter of the intermediate plate frame needs to be increased accordingly without reducing the internal space of the electrolyzer, that is, without reducing the inner diameter of the intermediate plate frame. Conventionally, when the outer diameter of the intermediate plate frame increases, the circumferential diameter of the tension bolts 4 needs to be increased accordingly. Accordingly, in order to fix the two ends of the tension bolts 4, the diameter of the end pressure plate 2 also needs to be increased, but this will increase the material cost. Therefore, in order not to increase the production cost, the present application chooses to set the avoidance gap 110 in the area on the outer circumferential surface of the intermediate plate frame that interferes with the tension bolts 4 without increasing the circumferential diameter of the tension bolts 4 and the diameter of the end pressure plate 2.

[0066] like Figure 7 and Figure 8As shown, in another embodiment, the outlet ends of the hydrogen collecting channel 102 and the oxygen collecting channel 101 and the inlet end of the electrolyte inlet 103 are connected with connecting pipes, and the end of the connecting pipe away from the intermediate plate frame is a flange structure, which can also achieve connection with external pipelines.

[0067] like Figure 1 and Fig.11 As shown, the remaining plate assemblies 3 located on both sides of the middle bipolar plate assembly 1 among the multiple plate assemblies 3 include at least two bipolar plate assemblies; each bipolar plate assembly includes a bipolar plate and a plate frame, the plate frame is arranged on the periphery of the bipolar plate, the two sides of the bipolar plate are an anode side and a cathode side, respectively, the anode side is opposite to the anode chamber, and the cathode side is opposite to the cathode chamber; at least one anode flow channel 303, at least one cathode flow channel 304, a hydrogen outlet flow channel 302 and an oxygen outlet flow channel 301 are arranged in the plate frame, the anode flow channel 303 and the cathode flow channel 304 are alternately arranged along the circumference of the plate frame, and the anode flow channel 303 is connected to the electrolyte anode distribution flow channel 104 in a one-to-one correspondence, the cathode flow channel 304 is connected to the electrolyte cathode distribution flow channel 105 in a one-to-one correspondence, the anode flow channel 303 and the oxygen outlet flow channel 301 are both connected to the anode chamber, and the cathode flow channel 304 and the hydrogen outlet flow channel 302 are both connected to the cathode chamber. Specifically, the anode flow channel 303 is connected to the anode chamber through an anode chamber groove 3031 arranged on one end face of the electrode frame close to the anode chamber, the cathode flow channel 304 is connected to the cathode chamber through a cathode chamber groove 3041 arranged on one end face of the electrode frame close to the cathode chamber, the oxygen outlet flow channel 301 is connected to the anode chamber through an oxygen groove 3011 arranged on one end face of the electrode frame close to the anode chamber, and the hydrogen outlet flow channel 302 is connected to the cathode chamber through a hydrogen groove 3021 arranged on one end face of the electrode frame close to the cathode chamber.

[0068] When the above technical solution is adopted, the electrolyte flows from the electrolyte cavity 112 of the intermediate plate frame, and a part of the electrolyte flows through the electrolyte anode distribution channel 104 to the anode flow channel 303 of each bipolar plate, and then enters each anode chamber through the anode flow channel 303. Figure 2 As shown by the solid arrow in the middle; oxygen is generated after electrolysis, and the oxygen enters the oxygen outlet flow channel 301 along with the electrolyte, and finally collects in the oxygen collection flow channel 101 of the intermediate plate frame, such as Figure 2 As shown by the dotted arrow in the middle, the electrolyte flows to the external oxygen pipe 5. Another part of the electrolyte flows to the cathode flow channel 304 of each bipolar plate through the electrolyte cathode distribution flow channel 105, and then enters each cathode chamber through the cathode flow channel 304. Figure 2 As shown by the solid arrow in the middle; hydrogen is generated after electrolysis, and the hydrogen enters the hydrogen outlet flow channel 302 along with the electrolyte, and finally gathers into the hydrogen collection flow channel 102 of the intermediate plate frame, such as Figure 2As shown by the dotted arrow in the middle, the hydrogen gas is discharged to the outside through a hydrogen pipeline 6. The entire electrolyte distribution flow channel and gas collection flow channel shorten the electrolyte and gas flow paths, improve the distribution uniformity, and the electrolyzer structure is compact.

[0069] Furthermore, in the present embodiment, the cross-sectional shape of the axial section of the electrolyte anode distribution channel 104 is the same as the cross-sectional shape of the anode channel 303, the cross-sectional shape of the axial section of the electrolyte cathode distribution channel 105 is the same as the cross-sectional shape of the cathode channel 304, the cross-sectional shape of the second axial section of the oxygen collecting channel 101 is the same as the cross-sectional shape of the oxygen outlet channel 301, and the cross-sectional shape of the second axial section of the hydrogen collecting channel 102 is the same as the cross-sectional shape of the hydrogen outlet channel 302, so as to reduce the sudden change of the flow cross-section, reduce the adverse effects of cavitation, erosion and the like on each channel, and avoid leakage.

[0070] In some embodiments, the bipolar plate has a thickness of 6-12 mm, preferably 7-11 mm, specifically 7 mm, 8 mm, 9 mm, 10 mm, 11 mm. Selecting a bipolar plate with a thickness less than 10 mm, for example, within the range of 7-10 mm, can further reduce the weight of the electrolyzer and reduce costs.

[0071] In some embodiments, a diaphragm is further provided between two adjacent plate assemblies 3, and the diaphragm is used to separate the anode chamber and the cathode chamber, so that the generated oxygen and hydrogen are separated and collected separately to improve the gas purity; the cathode chamber is composed of the cathode surface of the plate assembly 3, the support mesh and the cathode electrode mesh, and the anode chamber is composed of the anode surface of the plate assembly 3, the support mesh and the anode electrode mesh. The cathode surface and the anode surface of the bipolar plate are planes; the support mesh is a plate mesh structure, which is used to support the anode electrode mesh and the cathode electrode mesh, and is used for current transmission between the plate surface and the electrode mesh, and can be prepared by stamping a thin steel plate.

[0072] In other embodiments, the cathode chamber is composed of the cathode surface and cathode electrode mesh of the electrode plate assembly 3, and the anode chamber is composed of the anode surface and anode electrode mesh of the electrode plate assembly 3. The cathode surface and the anode surface have protrusions, which are used to support the cathode electrode mesh and the anode electrode mesh and transmit current, so that the electrode plates on both sides of the diaphragm can form a "top-to-top" form, forming reliable multi-point electrical contact, increasing the electrical contact area, and thus improving the hydrogen production efficiency.

[0073] In some possible implementations, a sealing gasket is further provided between two adjacent plate assemblies 3, the sealing gasket is located between one end of the plate assembly 3 and the diaphragm, and a hole is provided on the end face of the plate frame of the plate assembly 3, and the hole is used to release the compression of the sealing gasket. In this way, the sealing gasket can be partially embedded in the hole after compression to form a limit, so as to prevent the sealing gasket from being squeezed out of the electrolytic cell after compression, thereby affecting the sealing performance.

[0074] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0075] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. An electrolytic cell, characterized in that: The electrolytic cell comprises two end plates arranged along a first direction and a plurality of plate assemblies between the two end plates, wherein at least one of the plurality of plate assemblies is an intermediate bipolar plate assembly; an anode chamber and a cathode chamber are formed by sealing between two adjacent plate assemblies, and the anode chambers and the cathode chambers in the electrolytic cell are arranged alternately; The intermediate bipolar plate assembly comprises an intermediate plate frame and two flat plates, the two flat plates are parallel to each other and fixed at intervals on the edge of the intermediate plate frame, and the intermediate plate frame and the two flat plates enclose an electrolyte cavity; The intermediate electrode plate frame is provided with an electrolyte inlet, at least two electrolyte anode distribution channels and at least two electrolyte cathode distribution channels. The electrolyte inlet is arranged on the periphery of the intermediate electrode plate frame and is connected to the electrolyte cavity; the inlets of the electrolyte anode distribution channel and the electrolyte cathode distribution channel are both connected to the electrolyte cavity, the outlet of the electrolyte anode distribution channel is connected to the anode chamber, and the outlet of the electrolyte cathode distribution channel is connected to the cathode chamber; the electrolyte anode distribution channel and the electrolyte cathode distribution channel are alternately arranged along the circumference of the intermediate electrode plate frame.

2. The electrolytic cell according to claim 1, characterized in that The number of the electrolyte inlets is at least two, at least one of the electrolyte inlets is located in the middle of the intermediate electrode plate frame in the vertical direction, and the remaining electrolyte inlets are located in the upper and / or lower part of the intermediate electrode plate frame.

3. The electrolytic cell according to claim 1, characterized in that The electrolyte inlet penetrates the intermediate electrode plate frame along the radial direction of the intermediate electrode plate frame.

4. The electrolytic cell according to claim 1, characterized in that The electrolyte anode distribution channel and the electrolyte cathode distribution channel both include a radial section and an axial section, the radial section extends along the radial direction of the intermediate electrode plate frame, the axial section extends along the axial direction of the intermediate electrode plate frame and passes through the two end surfaces of the intermediate electrode plate frame, the two ends of the radial section are respectively connected to the electrolyte cavity and the axial section, the axial section of the electrolyte anode distribution channel is connected to the anode chamber, and the axial section of the electrolyte cathode distribution channel is connected to the cathode chamber.

5. The electrolytic cell according to claim 4, characterized in that The cross-section of the axial section perpendicular to the axial direction of the intermediate plate frame is circular, elliptical, waist-shaped or polygonal; the cross-section of the radial section is circular, elliptical or polygonal.

6. The electrolytic cell according to claim 1, characterized in that The at least two electrolyte anode distribution channels and the at least two electrolyte cathode distribution channels are located at the lower part of the intermediate plate frame.

7. The electrolytic cell according to claim 1, characterized in that The central angle between two of the at least two electrolyte anode distribution channels located at both ends is 60° to 180°, and / or the central angle between two of the at least two electrolyte cathode distribution channels located at both ends is 60° to 180°.

8. The electrolytic cell according to claim 1, characterized in that: A hydrogen collecting channel and an oxygen collecting channel are arranged on the upper part of the intermediate plate frame. The hydrogen collecting channel is communicated with the cathode chamber, and the oxygen collecting channel is communicated with the anode chamber.

9. The electrolytic cell according to claim 8, characterized in that There is at least one hydrogen collecting flow channel and at least one oxygen collecting flow channel, and the hydrogen collecting flow channel and the oxygen collecting flow channel are respectively located on both sides of the vertical diameter section of the intermediate plate frame.

10. The electrolytic cell according to claim 8, characterized in that The hydrogen collecting channel and the oxygen collecting channel both include a second radial section and a second axial section, the second radial section penetrates the outer peripheral surface of the intermediate electrode plate frame along the radial direction of the intermediate electrode plate frame, the second axial section extends along the axial direction of the intermediate electrode plate frame and penetrates the two end surfaces of the intermediate electrode plate frame, the second radial section is connected to the second axial section, the second axial section of the oxygen collecting channel is connected to the anode chamber, and the second axial section of the hydrogen collecting channel is connected to the cathode chamber.

11. The electrolytic cell according to claim 8, characterized in that The outlet ends of the hydrogen collecting flow channel and the oxygen collecting flow channel and the inlet end of the electrolyte inlet are flush with the outer peripheral surface of the intermediate plate frame; Or, flange surfaces are formed at positions of the outer peripheral surface of the intermediate plate frame corresponding to the outlet ends of the hydrogen collecting flow channel and the oxygen collecting flow channel and corresponding to the inlet end of the electrolyte inlet; Alternatively, the outlet ends of the hydrogen collecting channel and the oxygen collecting channel and the inlet end of the electrolyte inlet are all connected with connecting pipes, and one end of the connecting pipe away from the intermediate plate frame is a flange structure.

12. The electrolytic cell according to claim 1, characterized in that The remaining polar plate assemblies located on both sides of the middle bipolar plate assembly among the plurality of polar plate assemblies include at least two bipolar plate assemblies; The bipolar plate assembly comprises a bipolar plate and a plate frame, the plate frame is arranged at the periphery of the bipolar plate, the two sides of the bipolar plate are respectively an anode side and a cathode side, the anode side is opposite to the anode chamber, and the cathode side is opposite to the cathode chamber; At least one anode flow channel, at least one cathode flow channel, a hydrogen outlet flow channel and an oxygen outlet flow channel are arranged in the electrode plate frame, the anode flow channel and the cathode flow channel are alternately arranged along the circumference of the electrode plate frame, and the anode flow channel is connected to the electrolyte anode distribution flow channel in a one-to-one correspondence, the cathode flow channel is connected to the electrolyte cathode distribution flow channel in a one-to-one correspondence, the anode flow channel and the oxygen outlet flow channel are both connected to the anode chamber, and the cathode flow channel and the hydrogen outlet flow channel are both connected to the cathode chamber.

13. The electrolytic cell according to claim 1, characterized in that A diaphragm is also arranged between two adjacent electrode plate assemblies, and the diaphragm is used to separate the anode chamber from the cathode chamber; The cathode chamber is composed of the cathode surface of the electrode assembly, the support mesh and the cathode electrode mesh, and the anode chamber is composed of the anode surface of the electrode assembly, the support mesh and the anode electrode mesh; Alternatively, the cathode chamber is composed of the cathode surface and cathode electrode net of the electrode plate assembly, and the anode chamber is composed of the anode surface and anode electrode net of the electrode plate assembly, and the cathode surface and the anode surface have protrusions, and the protrusions are used to support the cathode electrode net and the anode electrode net.

14. The electrolytic cell according to claim 13, characterized in that A sealing gasket is also arranged between two adjacent plate assemblies, and the sealing gasket is located between one end of the plate assembly and the diaphragm. The end surface of the plate frame of the plate assembly is provided with a hole for releasing the compression of the sealing gasket.

15. The electrolytic cell according to claim 12, characterized in that The thickness of the bipolar plate is 7-10 mm.

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