ELECTROLYZER AND ELECTROLYTIC DEVICE THEREOF

Abstract

An electrolyzer includes a casing and an electrolytic device. The casing includes two side plates. The electrolytic device is disposed between the two side plates, and the electrolytic device includes a plurality of porous layers, a plurality of current collector plates, a plurality of membranes and a plurality of heating units. The current collector plates are arranged in an alternating manner with the porous layers. The membranes are disposed corresponding to the porous layers. The heating units are respectively disposed on at least some of the current collector plates.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. § 119 (a) on Patent Application No(s). 112151503 filed in Taiwan, R.O.C. on Dec. 29, 2023, the entire contents of which are hereby incorporated by reference.

TECHNICAL FIELD

This disclosure relates to an electrolyzer and an electrolytic device thereof.

BACKGROUND

With the growing global interest in renewable energy, electrolytic hydrogen production has gained significant attention in recent years. Conventional electrolyzers typically consist of a stacked structure with multiple porous layers and membranes arranged in series. Current collectors can serve as positive or negative electrodes, and the membranes can be either proton exchange membranes or anion exchange membranes.

SUMMARY

One embodiment of the disclosure provides an electrolyzer including a casing and an electrolytic device. The casing includes two side plates. The electrolytic device is disposed between the two side plates, and the electrolytic device includes a plurality of porous layers, a plurality of current collector plates, a plurality of membranes and a plurality of heating units. The current collector plates and the porous layers are arranged in an alternating manner.

The membranes are disposed corresponding to the porous layers. The heating units are respectively disposed on at least some of the current collector plates.

One embodiment of the disclosure provides an electrolytic device including two porous layers, two current collector plates, a membrane, at least one first heating unit and at least one second heating unit. The two porous layers are disposed between the two current collector plates. The membrane is disposed between the two porous layers. The first heating unit is disposed on one of the two current collector plates, and the second heating unit is disposed on other of the two current collector plates.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only and thus are not limitative of the present disclosure and wherein:

FIG. 1 is a block diagram of an electrolytic system in accordance with one embodiment of the disclosure;

FIG. 2 is a perspective view of an electrolyzer in accordance with one embodiment of the disclosure;

FIG. 3 is a cross-sectional view of the electrolyzer in FIG. 2;

FIG. 4 is an exploded view of an electrolytic device in accordance with one embodiment of the disclosure;

FIG. 5 is a cross-sectional view of an electrolyzer in accordance with another embodiment of the disclosure;

FIG. 6 is an exploded view of an electrolytic device in accordance with another embodiment of the disclosure;

FIG. 7 is a schematic diagram illustrating a signal communication between a temperature sensor, a control unit and a heating unit in accordance with one embodiment of the disclosure where the control unit is configured for controlling the operation of a thermoelectric component; and

FIG. 8 is a plot showing the temperature rise of an electrolyte in one embodiment of the disclosure and that in a comparative example.

DETAILED DESCRIPTION

Aspects and advantages of the invention will become apparent from the following detailed descriptions with the accompanying drawings. For purposes of explanation, one or more specific embodiments are given to provide a thorough understanding of the invention, and which are described in sufficient detail to enable one skilled in the art to practice the described embodiments. It should be understood that the following descriptions are not intended to limit the embodiments to one specific embodiment. On the contrary, it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the described embodiments as defined by the appended claims.

Please refer to FIG. 1, which is a block diagram of an electrolytic system in accordance with one embodiment of the disclosure. In this embodiment, an electrolytic system ES includes an electrolyzer 1, an electrolyte storage tank 2 and a heat exchanger 3. The electrolyte storage tank 2 stores an electrolyte, and the electrolyte may be, but is not limited to, pure water or an aqueous solution containing alkaline ion compounds. Moreover, the electrolyzer 1 can utilize either anion exchange membrane (AEM) or proton exchange membrane (PEM) water electrolysis hydrogen production technology. The electrolyte can flow into the electrolyzer 1 through a channel C1, and the electrolyte undergoes electrolysis to produce hydrogen and oxygen in the electrolyzer 1. The hydrogen generated in the electrolyzer 1 can be transported to the hydrogen storage unit (not shown) through a channel C2, and the oxygen and the electrolyte in the electrolyzer 1 can be directed to the electrolyte storage tank 2 through a channel C3. The oxygen can be discharged from the electrolytic system ES through another channel (not shown) connected to the electrolyte storage tank 2. The heat exchanger 3 may include heat management devices such as heat sinks or water cooling devices. The heat exchanger 3 is configured to cool the electrolyte to regulate the temperature of the electrolyte.

The configuration of the electrolyzer 1 will be described in the subsequent paragraphs. Please refer to FIG. 2 to FIG. 4. FIG. 2 is a perspective view of an electrolyzer in accordance with one embodiment of the disclosure, FIG. 3 is a cross-sectional view of the electrolyzer in FIG. 2, and FIG. 4 is an exploded view of an electrolytic device in accordance with one embodiment of the disclosure. In this embodiment, the electrolyzer 1 includes a casing 10 and an electrolytic device 20.

The casing 10 includes two end plates. Specifically, the casing 10 includes a left end plate 110 and a right end plate 120. The left end plate 110 or the right end plate 120 may have a fluid port that connects to the electrolyte storage tank. For example, referring to FIG. 1 and FIG. 2, the left end plate 110 may have two fluid ports 111 and 112. The fluid port 111 can be connected to the electrolyte storage tank 2 through the channel C1, and the fluid port 112 can be connected to the electrolyte storage tank 2 through channel C3, allowing the electrolyte to flow between the electrolyzer 1 and the electrolyte storage tank 2. In addition, the casing 10 may further include at least one connection rod 130 fixed to both the left end plate 110 and the right end plate 120 to maintain a spacing between the left end plate 110 and the right end plate 120.

As shown in FIG. 4, the electrolytic device 20 in FIG. 3 may substantially include a plurality of porous layers and a plurality of current collector plates. In this embodiment, the electrolytic device 20 includes a plurality of porous layers 210, a plurality of current collector plates 220 and a plurality of membranes 230. In another embodiment, the electrolytic device 20 may include two porous layers 210, two current collector plates 220 and one membrane 230. FIG. 3 schematically illustrates multiple porous layers 210, current collector plates 220 and membranes 230 arranged in an alternating manner. Specifically, along a direction A1 from the left end plate 110 towards the right end plate 120, the aforementioned components are arranged in the following order: the current collector plate 220, the porous layer 210, the membrane 230, the porous layer 210 and the current collector plate 220. The porous layers 210 may be made of titanium or nickel, but the present disclosure is not limited to these materials. The current collector plates 220 may be made of stainless steel, but the present disclosure is not limited to the material. In this embodiment, the current collector plates 220 may be bipolar plates. Additionally, in this embodiment, the membranes 230 may be anion exchange membranes disposed corresponding to the porous layers 210, more specifically, between two of the porous layers 210.

The electrolytic device 20 further includes a plurality of heating units 240 respectively disposed on at least some of the current collector plates 220. In this embodiment, each of the current collector plates 220 is provided with the heating unit 240. Specifically, the heating units 240 can be joined to the current collector plates 220 by laser welding or ultrasonic welding. The heating units 240 may be thermoelectric components each including a thermoelectric material. When a voltage is applied to the heating units 240, the heating units 240 heat the current collector plates 220, thereby heating the electrolyte in the electrolyzer 1 through the heated current collector plates 220. Examples of the thermoelectric material include, but are not limited to, bismuth telluride, lead telluride, and silicon-germanium alloy.

In this embodiment, each of the membranes 230 of the electrolytic device 20 may include a catalyst material. The catalyst material may include, but is not limited to, graphene or iridium oxide. In this embodiment, the catalyst material is in the form of a catalyst coating on the surface of the membrane 230, but the disclosure is not limited thereto. In some embodiments, the catalyst material may be catalyst micrometer particles or catalyst nanoparticles distributed on the surface of or within the membrane 230.

In this embodiment, the electrolytic device 20 may include two current collector plates 220 and two porous layers 210 located between the two current collector plates 220. The current collector plates 220 each may have a plurality of liquid supply holes 221, and the porous layers 210 each may have a plurality of liquid supply holes 231. Some of the liquid supply holes 231 and some of the liquid supply holes 221 may be connected to the fluid port 111 of the left end plate 110, and other of the liquid supply holes 231 and other of the liquid supply holes 221 may be connected to the fluid port 112 of the left end plate 110, allowing the electrolyte to flow within the electrolyzer 1.

In this embodiment, each of the current collector plates 220 may include a tab 222, and the heating units 240 are disposed on the tabs 222. Referring to FIG. 3 and FIG. 4, the current collector plates 220 each may include a tab 222 extending beyond an edge of the porous layer 210 disposed adjacent thereto. More specifically, in this embodiment, the tab 222 of each current collector plate 220 may extend beyond the edge of the porous layer 210 that is adjacent to the current collector plate 220. More specifically, the tab 222 may not overlap the porous layer 210 in the direction A1 shown in FIG. 3. The structural design of placing the heating units 240 on the tabs 222 allows the thickness of the electrolyzer 1 in the direction A1 to be reduced.

In this embodiment, the electrolyzer 1 may further include an insulator disposed between the current collector plate 220 and the heating unit 240. The insulator is configured to prevent the voltage applied to the heating unit 240 from being accidentally applied to the current collector plate 220, thereby ensuring the operational stability of the electrolyzer 1.

As shown in FIG. 1 to FIG. 4, the electrolyte can flow into the electrolyzer 1 via the fluid port 111 of the left end plate 110. The electrolyte within the electrolyzer 1 can flow to the membrane 230 through the liquid supply hole 231 of the porous layer 210 and the liquid supply hole 221 of the current collector plate 220 to undergo chemical reactions, generating hydrogen and oxygen. The electrolyte and the oxygen can flow out of the electrolyzer 1 through the fluid port 112 of the left end plate 110, and the hydrogen can be discharged from the electrolyzer 1 through another path (e.g., the channel C2 as shown in FIG. 1).

The electrolytic devices of the present disclosure are not limited to the configuration of the electrolytic device 20 in FIG. 2 and FIG. 3. In some embodiments, the electrolytic device may include only two porous layers, only two current collector plates, only one membrane, and one or more heating units depending on the specific dimensions of the electrolyzer.

According to the electrolyzer 1 and the electrolytic device 20 thereof as described above, the heating units 240 are disposed on the current collector plates 220. Compared to conventional electrolytic systems without heaters or with heaters disposed outside the electrolyzer, the heating units 240 in this embodiment can rapidly increase the temperature of the electrolyte within the electrolyzer 1, thereby effectively meeting the demand for high power generation from renewable energy and achieving stable hydrogen storage efficiency.

In the electrolyzer 1 as shown in FIG. 3, each of the current collector plates 220 is provided with the heating unit 240, but the present disclosure is not limited thereto. Please refer to FIG. 5, which is a cross-sectional view of an electrolyzer in accordance with another embodiment of the disclosure. In this embodiment, the electrolyzer 1A includes a casing 10 and an electrolytic device 20A. The electrolyzer 1A in this embodiment is similar to the electrolyzer 1 in FIG. 3, and the following will focus on the differences between them, with similarities or identities being omitted for brevity.

In this embodiment, the electrolytic device 20A includes a plurality of porous layers 210 and a plurality of current collector plates, and the porous layers 210 and the current collector plates are arranged in an alternating manner. Specifically, the current collector plates of the electrolytic device 20A include a plurality of first current collector plates 220a and a plurality of second current collector plates 220b. Along the direction Al from the left end plate 110 towards the right end plate 120, the aforementioned components are arranged in the following order: the first current collector plate 220a, the porous layer 210, the membrane 230, the porous layer 210, the second current collector plate 220b, the porous layer 210, the membrane 230 and the porous layer 210. The second current collector plates 220b are respectively located between two of the first current collector plates 220a. The tabs 222 of the first current collector plates 220a are each provided with the heating unit 240, and none of the second current collector plates 220b is provided with the heating unit 240.

Therefore, the heating unit 240 on any of the current collector plates can be prevented from being in thermal contact with adjacent current collector plates.

In the electrolytic device 20 as shown in FIG. 4, each of the current collector plates 220 is provided with one heating unit 240, but the present disclosure is not limited thereto. Please refer to FIG. 6, which is an exploded view of an electrolytic device in accordance with another embodiment of the disclosure. In this embodiment, the electrolytic device 20B includes a plurality of porous layers 210, a plurality of current collector plates 220 and a plurality of heating units 240.

In this embodiment, one or more of the current collector plates 220 are each provided with multiple heating units 240. As shown in FIG. 6, each of the current collector plates 220 is provided with four heating units 240, and the heating units 240 are arranged, spaced apart from each other, in a circumferential direction of the current collector plate 220. Specifically, each of the current collector plates 220 may include a plurality of tabs 222, and the heating units 240 are respectively disposed on the tabs 222. Therefore, a more uniform and efficient temperature rise of each current collector plate 220 can be provided.

According to the present disclosure, the electrolyzer can be optionally provided with a temperature sensor and a control unit to achieve feedback control of the heating unit. Please refer to FIG. 7, which is a schematic diagram illustrating a signal communication between a temperature sensor, a control unit and a heating unit in accordance with one embodiment of the disclosure where the control unit is configured for controlling the operation of a thermoelectric component. The electrolyzer 1 in FIG. 1 to FIG. 3 may further include a temperature sensor 40 and a control unit 50. The temperature sensor 40 is configured to sense the temperature of the electrolyte, the porous layers 210 or the current collector plates 220 to obtain a temperature value. Specifically, the temperature sensor 40 may be disposed on the electrolyte storage tank 2 or the channel C3 to sense the temperature of the electrolyte, or disposed in the electrolyzer 1 to sense the temperature of the porous layers 210 or the current collector plates 220.

The electrolyzer 1A in FIG. 5 may also include a temperature sensor 40 and a control unit 50. The temperature sensor 40 may be disposed in the electrolyzer 1A to sense the temperature of the porous layers 210 or the first current collector plates 220a.

The control unit 50 is, for example but not limited to, an application-specific integrated circuit (ASIC) in signal communication with the temperature sensor 40 to receive the temperature value obtained by the temperature sensor 40. The control unit 50 is further in signal communication with the heating unit 240, such that the control unit 50 may control the operation of the heating unit 240 based on the temperature value. Specifically, when the temperature of a sensed object (e.g., the electrolyte, porous layers 210 or current collector plates 220) is too low, the control unit 50 activates the heating unit 240 to enhance the hydrogen production efficiency of the electrolyzer 1. Conversely, when the temperature of a sensed object is too high, the control unit 50 either reduces the power output of the heating unit 240 or stops the operation of the heating unit 240 to prevent the electrolyte from being overheated.

In the electrolyzer 1 as shown in FIG. 3, the heating units 240 can rapidly increase the temperature of the electrolyte. Please refer to FIG. 8, which is a plot showing the temperature rise of an electrolyte in one embodiment of the disclosure and that in a comparative example. According to one comparative example, a conventional electrolytic system typically employs a conventional heating method where heaters are disposed outside of an electrolyzer (e.g., disposed on an electrolyte storage tank or a channel through which an electrolyte passes). According to one embodiment of the present disclosure, an electrolytic system employs a novel heating method where heaters are disposed on a current collector plate; for example, the electrolytic system ES in FIG. 1 may include the electrolyzer 1 where the heating units 240 are disposed on the current collector plates 220.

Taking the heating of the electrolyte from 25° C. to 55° C. as an example, the conventional heating method takes approximately 30 minutes to complete. In contrast, the novel heating method requires only about 5 minutes. Therefore, compared to the comparative example, the electrolytic system according to one embodiment of the present disclosure can more rapidly increase the temperature of the electrolyte to a level that maximizes hydrogen production.

According to the electrolyzer and the electrolytic device thereof as described above, the heating units are disposed on the current collector plates. The heating units are capable of rapidly increasing the temperature of the electrolyte within the electrolyzer, thereby effectively meeting the demand for high power generation from renewable energy and achieving stable hydrogen storage efficiency.

The embodiments were chosen and described in order to best explain the principles of the disclosure and its practical applications, to thereby enable others skilled in the art to best utilize the disclosure and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the disclosure be defined by the following claims and their equivalents.

Claims

1. An electrolyzer comprising: a casing comprising two side plates; andan electrolytic device disposed between the two side plates, and the electrolytic device comprising: a plurality of porous layers;a plurality of current collector plates arranged in an alternating manner with the plurality of porous layers;a plurality of membranes disposed corresponding to the plurality of porous layers; anda plurality of heating units respectively disposed on at least some of the plurality of current collector plates.

2. The electrolyzer according to claim 1, wherein each of the plurality of current collector plates comprises a tab, and the plurality of heating units are respectively disposed on at least some of the tabs.

3. The electrolyzer according to claim 2, wherein the plurality of heating units are respectively disposed on each of the tabs of the plurality of current collector plates.

4. The electrolyzer according to claim 2, wherein the plurality of current collector plates comprises two first current collector plates and a second current collector plate, the second current collector plate is located between the two first current collector plates, each of the two first current collector plates is provided with one of the plurality of heating units, and the second current collector plate is not provided with any of the plurality of heating units.

5. The electrolyzer according to claim 1, wherein two or more of the plurality of heating units are disposed on one of the plurality of current collector plates.

6. The electrolyzer according to claim 1, further comprising a temperature sensor and a control unit, wherein the control unit is in signal communication with the temperature sensor and the plurality of heating units, the temperature sensor is configured to sense a temperature of an electrolyte, the plurality of porous layers, or the plurality of current collector plates to obtain a temperature value, and the control unit is configured to control an operation of the plurality of heating units based on the temperature value.

7. The electrolyzer according to claim 1, wherein each of the plurality of membranes comprises a catalyst material.

8. The electrolyzer according to claim 1, wherein each of the plurality of membranes is an anion exchange membrane.

9. An electrolytic device comprising: two porous layers;two current collector plates, wherein the two porous layers are disposed between the two current collector plates;a membrane disposed between the two porous layers;at least one first heating unit disposed on one of the two current collector plates; andat least one second heating unit disposed on other of the two current collector plates.

10. The electrolytic device according to claim 9, wherein each of the two current collector plates comprises a tab, and the at least one first heating unit and the at least one second heating unit are respectively disposed on the tabs of the two current collector plates.

11. The electrolytic device according to claim 10, wherein the tabs extend beyond an edge of each of the two porous layers.

12. The electrolytic device according to claim 9, wherein the at least one first heating unit comprises a plurality of first heating units, the at least one second heating unit comprises a plurality of second heating units, the plurality of first heating units are arranged, spaced apart from each other, in a circumferential direction of one of the two current collector plates, and the plurality of second heating units are arranged, spaced apart from each other, in a circumferential direction of other of the two current collector plates.

13. The electrolytic device according to claim 9, wherein the membrane is an anion exchange membrane.

14. The electrolytic device according to claim 9, wherein the membrane comprises a catalyst material.