Decoupling electrolytic water hydrogen production electrolytic tank

Abstract

The invention discloses a decoupling electrolytic water hydrogen production electrolytic tank, and relates to the technical field of water electrolysis. The device comprises end plates located at the two ends, wherein N partition plates and N + 1 bipolar electrode plates are arranged between the two end plates; the partition plates and the bipolar electrode plates are alternately arranged; the bipolar electrode plate comprises a nickel plate layer, a nickel hydroxide layer and a nickel oxyhydroxide layer are arranged on the two sides of the nickel plate layer respectively, insulating diaphragms are arranged on the outer sides of the nickel hydroxide layer and the nickel oxyhydroxide layer respectively, and an electrode A and an electrode B are arranged on the outer sides of the two insulating diaphragms respectively. Gas is isolated through the partition plate, meanwhile, the nickel hydroxide layer and the nickel oxyhydroxide layer are arranged on the two sides of the partition plate respectively, the positive electrode and the negative electrode of a power source are switched through the two electrode ends, and hydrogen production and oxygen production are completed in different spaces in one device system at the same time.

Description

Technical Field

[0001] The invention belongs to the technical field of water electrolysis, and in particular relates to a decoupled water electrolysis hydrogen production electrolytic cell. Background Art

[0002] In order to solve the increasingly intensified contradiction between economic development and energy shortage and environmental pollution, it has become a very urgent task to develop clean, efficient and sustainable new energy power technology. The development of renewable energy and the clean and efficient use of energy will be an important practical issue facing the international community today. Hydrogen energy, as an efficient, clean and ideal secondary energy source, has received widespread attention from all over the world. Large-scale and cheap production of hydrogen is one of the important links in the development and utilization of hydrogen energy.

[0003] For example, China Publication No. CN105734600B discloses a device and method for producing hydrogen by electrolyzing water in a two-step method with a three-electrode system and dual electrolyzers. The electrolysis device comprises two independent electrolyzers (slot 1 and slot 2), a hydrogen evolution catalytic electrode, an oxygen evolution catalytic electrode, a nickel hydroxide electrode, and an alkaline electrolyte. The electrolysis device divides the water electrolysis process into two steps, hydrogen production and oxygen production, and performs the steps alternately in two electrolyzers (slot-1 and slot-2); hydrogen and oxygen cannot be produced simultaneously, and the production efficiency is slow. Summary of the invention

[0004] The object of the present invention is to provide a decoupled water electrolysis hydrogen production electrolyzer, in which gas is isolated by a partition, and a nickel hydroxide layer and a nickel oxyhydroxide layer are respectively arranged on both sides of the partition, and the positive and negative poles of the power supply are switched through two electrode ends, so that hydrogen and oxygen production are completed synchronously in separate chambers during use, thereby improving production efficiency and safety.

[0005] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0006] The present invention is a decoupled water electrolysis hydrogen production electrolyzer, comprising end plates located at both ends, wherein N partitions and N+1 bipolar electrode plates are arranged between the two end plates; the partitions and the bipolar electrode plates are arranged alternately; the bipolar electrode plates include a nickel plate layer, wherein a nickel hydroxide layer and a nickel oxyhydroxide layer are respectively arranged on both sides of the nickel plate layer, and insulating diaphragms are arranged on the outer sides of the nickel hydroxide layer and the nickel oxyhydroxide layer, and electrodes A and electrodes B are respectively arranged on the outer sides of the two insulating diaphragms.

[0007] Furthermore, the electrode A and the electrode B are both nickel mesh or nickel foam.

[0008] Furthermore, the end plate is made of a nickel plate or a stainless steel plate, and the partition is made of a steel plate or a nickel-plated steel plate.

[0009] Furthermore, the two end plates are respectively connected to the positive pole and the negative pole of the power supply.

[0010] Furthermore, an exhaust port A and an exhaust port B are respectively provided at the top of the two end plates of the electrolytic cell; an electrolysis chamber is formed between two adjacent partitions, or between the partition and the end plate, and the bipolar electrode plate divides the electrolysis chamber into a first chamber and a second chamber located on both sides of the bipolar electrode plate; the exhaust port A is connected to the first chamber, and the second chamber is connected to the exhaust port B.

[0011] Furthermore, a first alkali solution supplement channel and a second alkali solution supplement channel are respectively connected at the bottom positions of the two end plates of the electrolytic cell, and the first alkali solution supplement channel and the second alkali solution supplement channel are respectively connected to the first cavity and the second cavity.

[0012] The present invention has the following beneficial effects:

[0013] The present invention isolates the gas through a partition, and simultaneously arranges a nickel hydroxide layer and a nickel oxyhydroxide layer on both sides of the partition, and switches the positive and negative poles of the power supply through two electrode ends, thereby achieving hydrogen and oxygen production in different spaces within one device system at the same time.

[0014] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0016] Figure 1 It is a schematic diagram of the structure of the electrolytic cell of the present invention;

[0017] Figure 2 It is a schematic diagram of the structure of the bipolar electrode plate of the present invention. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inside", "all around" and the like indicating orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0020] See also Figure 1 As shown, the present invention is a decoupled water electrolysis hydrogen production electrolyzer, which includes two end plates 1 located at both ends respectively, and five partitions 3 and six bipolar electrode plates 2 are arranged between the two end plates 1. When installed, the five partitions 3 and the six bipolar electrode plates 2 are arranged alternately, and the bipolar electrode plates 2 are located inside the electrolysis chamber formed between two adjacent partitions 3, or between the partition 3 and the end plate 1, and the bipolar electrode plates 2 divide the electrolysis chamber into a first chamber and a second chamber located on both sides of the bipolar electrode plates 2.

[0021] Specifically, Figure 2 As shown, the bipolar electrode plate 2 provided by the present invention includes a nickel plate layer 20, and a nickel hydroxide layer 21a and a nickel oxyhydroxide layer 21b are respectively arranged on both sides of the nickel plate layer 20, and insulating membranes 22 are arranged on the outside of the nickel hydroxide layer 21a and the nickel oxyhydroxide layer 21b, and electrodes A24 and electrode B23 are respectively arranged on the outside of the two insulating membranes 22.

[0022] Then when using, Figure 1 As shown, when the left and right end plates 1 are connected to the positive and negative poles of the power supply respectively, the reaction occurring in the left electrode A24 region is:

[0023] The nickel oxyhydroxide layer 21b at the electrode A24 as the cathode reacts as follows:

[0024] 4NiOOH+2H2O→4Ni(OH)2+O2;

[0025] At the same time, the reaction of the nickel hydroxide layer 21a at the anode electrode B23 is: Ni(OH)2+OH–→N iOOH+H2O+e–: Synchronously, the reaction in the electrolyte at the electrode B23 is: 4H2O+4e–→4OH–+2H2;

[0026] After one electrolysis is completed, the positive and negative electrodes of the power supply connected to the left and right end plates 1 are switched. At this time, the reaction occurring in the electrode A24 region as the anode is:

[0027] N i(OH)2+OH–→N iOOH+H2O+e–: 4H2O+4e–→4OH–+2H2 occurs in the electrolyte at the synchronous electrode A24;

[0028] At the same time, the reaction occurring at electrode B23 serving as the cathode is: 4NiOOH+2H2O→4Ni(OH)2+O2.

[0029] In the present invention, the insulating diaphragm 22 is used to insulate, and the partition plate 3 is used to isolate the gas; the partition plate 3 is a steel plate or a nickel-plated steel plate; and the material of the end plate 1 is a nickel plate or a stainless steel plate.

[0030] Based on the above use, in order to facilitate the discharge of hydrogen and oxygen generated by electrolysis during use, the present invention provides an exhaust port A13 and an exhaust port B14 at the top of the two end plates 1 of the electrolytic cell respectively; the exhaust port A13 is connected to the first cavity, the second cavity is connected to the exhaust port B14, and the exhaust port A13 is connected to the air inlet end of a valve A with two outlet ends, and the exhaust port B14 is connected to the air inlet end of a valve B with two outlet ends, and the two outlet ends of the valve B are respectively connected to the hydrogen storage tank and the oxygen storage tank, and the two outlet ends of the valve A are respectively connected to the hydrogen storage tank and the oxygen storage tank.

[0031] Then, during the electrolysis process, it is convenient to use Figure 1 As shown, when the left and right end plates 1 are connected to the positive and negative poles of the power source respectively, a first cavity and a second cavity are formed on the left and right sides of the bipolar electrode plate 2 .

[0032] At this time, by controlling the switching of valve A and valve B, the oxygen produced in the first chamber is sent to the oxygen storage tank, and the hydrogen produced in the second chamber is sent to the hydrogen storage tank; at the same time, after completing one electrolysis, the positive and negative poles of the power supply connected to the left and right end plates 1 are controlled to switch, and valve A and valve B are synchronously controlled to switch, so that the oxygen produced in the second chamber is sent to the oxygen storage tank, and the hydrogen produced in the first chamber is sent to the hydrogen storage tank.

[0033] The bottom positions of the two end plates 1 of the electrolytic cell are respectively connected with a first alkali solution replenishing channel 10 and a second alkali solution replenishing channel 11, which are respectively connected to the first cavity and the second cavity; after completing one electrolysis, the first alkali solution replenishing channel 10 and the second alkali solution replenishing channel 11 are used to replenish the lost electrolyte into the first cavity and the second cavity.

[0034] The electrolyte in the present invention is a KOH solution.

[0035] like Figure 1As shown, in the present invention, a plurality of protrusions are provided on the inner wall of the end plate 1 and both sides of the partition 3. By utilizing the setting of the protrusions, when the end plate 1 and the partition 3 are in contact with the bipolar electrode plate 2 during use, a gap is formed between the end plate 1 and the partition 3 and the bipolar electrode plate 2 to improve the unconstrained flow direction of the electrolyte in the electrolysis chamber, reduce the lateral cross-flow of the electrolyte, and facilitate to carry away the generated gas faster, thereby increasing the electrolysis efficiency.

[0036] In the process of water electrolysis, hydrogen evolution reaction and oxygen evolution reaction are coupled in time and space. Whether it is alkaline solution electrolysis of water, proton / anion exchange membrane electrolysis of water, or solid oxide electrolysis of water, it is necessary to use a corresponding diaphragm to block the mixing of hydrogen and oxygen to ensure the purity of hydrogen and oxygen; in the present invention, the hydrogen evolution reaction and the oxygen evolution reaction are independent in time, that is, hydrogen is diffused in the entire electrolyzer during the hydrogen evolution reaction, and oxygen is diffused in the entire electrolyzer during the oxygen evolution reaction; this requires controlling the gas to be able to pass through the diaphragm freely, and then the diaphragm provided by the present invention is a porous insulating film; when it is used, it ensures that the gas can pass through the diaphragm, and then no pressure difference is formed on both sides of the diaphragm during use, so that the high purity of the gas can be guaranteed under high pressure and renewable energy power supply, and the multi-faceted benefits of high-pressure water electrolysis are obtained, and it is more suitable for the power fluctuation of wind and solar power plants.

[0037] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0038] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A decoupled water electrolysis hydrogen production electrolyzer, characterized in that: It comprises end plates (1) located at both ends, and N separators (3) and N+1 bipolar electrode plates (2) are arranged between the two end plates (1); The separators (3) and the bipolar electrode plates (2) are arranged alternately; The bipolar electrode plate (2) comprises a nickel plate layer (20), a nickel hydroxide layer (21a) and a nickel oxyhydroxide layer (21b) are respectively arranged on both sides of the nickel plate layer (20), an insulating diaphragm (22) is arranged on the outer sides of the nickel hydroxide layer (21a) and the nickel oxyhydroxide layer (21b), and an electrode A (24) and an electrode B (23) are respectively arranged on the outer sides of the two insulating diaphragms (22).

2. A decoupled water electrolysis hydrogen production electrolyzer according to claim 1, characterized in that: The electrode A (24) and the electrode B (23) are both nickel mesh or nickel foam.

3. A decoupled water electrolysis hydrogen production electrolyzer according to claim 1, characterized in that: The material of the end plate (1) is a nickel plate or a stainless steel plate, and the partition plate (3) is a steel plate or a nickel-plated steel plate.

4. A decoupled water electrolysis hydrogen production electrolyzer according to claim 1, characterized in that: The two end plates (1) are respectively connected to the positive pole and the negative pole of the power supply.

5. The decoupled water electrolysis hydrogen production electrolyzer according to claim 1, characterized in that: An exhaust port A (13) and an exhaust port B (14) are respectively provided at the top of the two end plates (1) of the electrolytic cell; An electrolysis chamber is formed between two adjacent separators (3) or between the separator (3) and the end plate (1), and the bipolar electrode plate (2) divides the electrolysis chamber into a first chamber and a second chamber located on both sides of the bipolar electrode plate (2); The exhaust port A (13) is communicated with the first cavity, and the second cavity is communicated with the exhaust port B (14).

6. The decoupled water electrolysis hydrogen production electrolyzer according to claim 1, characterized in that: The bottom positions of the two end plates (1) of the electrolytic cell are respectively connected with a first alkali solution replenishing channel (10) and a second alkali solution replenishing channel (11), and the first alkali solution replenishing channel (10) and the second alkali solution replenishing channel (11) are respectively connected to the first cavity and the second cavity.

Images