Thermal management subsystem for electrolysis system and electrolysis system

Abstract

The utility model provides a thermal management subsystem for an electrolysis system. The thermal management subsystem is configured to be capable of switching between a heating loop and a cooling loop. The heating loop comprises a compressor and a condenser, the condenser is used for being connected to a supply pipeline of the electrolysis system, and the compressor is used for driving the refrigerant to circulate along the heating loop, so that the refrigerant releases heat when flowing through the condenser to heat the electrolyte conveyed through the supply pipeline. The cooling loop comprises the same compressor and evaporator, the evaporator is used for being connected to the discharge pipeline, and the compressor is used for driving the refrigerant to circulate along the cooling loop, so that the refrigerant absorbs heat when flowing through the evaporator to cool reaction products conveyed through the discharge pipeline. The thermal management subsystem provided by the utility model can provide relatively high heating and cooling efficiency, so that the energy consumption is remarkably reduced, and the energy utilization efficiency of the electrolysis system is improved. The utility model further provides an electrolysis system comprising the thermal management subsystem.

Description

TECHNICAL FIELD

[0001] The present application relates generally to the technical field of electrolysis and thermal management, and in particular to a thermal management subsystem for an electrolysis system and an electrolysis system comprising such a thermal management subsystem. BACKGROUND

[0002] Hydrogen has a wide range of applications, covering chemical industry, energy, transportation, electronics and many other fields. There are many ways to produce hydrogen at present, among which electrolysis technology has become a research hotspot in the field of hydrogen production. Taking an alkaline solution electrolysis system as an example, the electrolyte is delivered to the electrolysis device via a supply pipeline, and the water in the electrolyte is electrolyzed in the electrolysis device. The reaction products (hydrogen and oxygen) and the unconsumed electrolyte from the electrolysis device are delivered via a discharge pipeline and separated from each other. The reaction products are then purified and stored, and the unconsumed electrolyte is delivered to the electrolysis device again via the supply pipeline. The electrolysis system also comprises a thermal management subsystem for controlling and regulating the temperature of each component or part in the electrolysis system, so as to ensure efficient and stable hydrogen production.

[0003] In the case where, for example, the electrolysis system is in the starting stage, the electrolyte to be supplied to the electrolysis device needs to be heated to quickly raise the temperature in the electrolysis device to a range suitable for the electrolysis reaction. To this end, the thermal management subsystem comprises an electric heater which can be arranged on the supply pipeline and heats the electrolyte when powered on. In addition, when the electrolysis system is running normally, the electrolysis system produces hydrogen at high power, and a large amount of heat generated by the electrolysis reaction causes the temperature of the reaction products output from the electrolysis device to be high. In this case, the reaction products need to be cooled to facilitate their separation from the electrolyte, in particular from the water contained in the electrolyte. To this end, the thermal management subsystem comprises a semiconductor refrigerator which can be arranged on the discharge pipeline and cools the reaction products when powered on. However, the electric heater and the semiconductor refrigerator consume a large amount of electric energy, resulting in high energy consumption of the thermal management subsystem and thus reducing the energy utilization efficiency of the electrolysis system.

[0004] Therefore, there is an urgent need to improve the thermal management subsystem of the electrolysis system to overcome the above-mentioned defects. INVENTION CONTENTS

[0005] The present application aims to provide a thermal management subsystem and a corresponding electrolysis system to overcome at least one of the above-mentioned defects in the prior art.

[0006] In one aspect, the present application provides a thermal management subsystem for an electrolysis system. The electrolysis system includes an electrolysis device for electrolyzing water in an electrolyte, a feed line for delivering electrolyte to the electrolysis device, and a discharge line for delivering reaction products from the electrolysis device, the thermal management subsystem being configured to switch between a heating loop and a cooling loop, wherein: the heating loop includes a compressor and a condenser, the condenser is for connection to the feed line, and the compressor is for driving circulation of a refrigerant along the heating loop such that the refrigerant releases heat when flowing through the condenser to heat electrolyte delivered via the feed line; and the cooling loop includes the compressor and an evaporator, the evaporator is for connection to the discharge line, and the compressor is for driving circulation of the refrigerant along the cooling loop such that the refrigerant absorbs heat when flowing through the evaporator to cool reaction products delivered via the discharge line.

[0007] In some embodiments, the thermal management subsystem further includes: a refrigerant circulation circuit including a main leg and first and second branch legs connected in parallel to the main leg, the compressor being connected to the main leg, the condenser being connected to the first branch leg, and the evaporator being connected to the second branch leg; and a circuit switching mechanism configured to selectively access the first or second branch leg to the main leg; wherein the thermal management subsystem is switched to the heating loop when the first branch leg is accessed to the main leg, and the thermal management subsystem is switched to the cooling loop when the second branch leg is accessed to the main leg.

[0008] In some embodiments, the condenser is a first condenser and the evaporator is a second evaporator; the thermal management subsystem further includes a first expansion valve and a first evaporator, both connected to the first branch leg; and when the first branch leg is accessed to the main leg, the refrigerant circulates in the main leg and the first branch leg in an order of sequentially passing through the compressor, the first condenser, the first expansion valve, and the first evaporator.

[0009] In some embodiments, the electrolysis system further includes a primary gas-liquid separator for receiving and separating reaction products and unconsumed electrolyte from the electrolysis device and storing electrolyte, the feed line includes a first section for delivering electrolyte from the primary gas-liquid separator to the electrolysis device, and the first condenser is for connection to the first section of the feed line.

[0010] In some embodiments, the electrolysis system further comprises a primary gas-liquid separator for receiving and separating reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, the feed line comprises a second section for transporting water from a water source to the primary gas-liquid separator or the electrolysis device, and the first condenser is configured to be connected on the second section of the feed line.

[0011] In some embodiments, the condenser is a first condenser and the evaporator is a second evaporator; the thermal management subsystem further comprises a second condenser and a second expansion valve, both connected on the second branch; and when the second branch is tapped into the main loop, the refrigerant circulates in the main loop and the second branch in the order of sequentially passing through the compressor, the second condenser, the second expansion valve, and the second evaporator.

[0012] In some embodiments, the exhaust line comprises a first exhaust line for transporting hydrogen-side reaction products from the electrolysis device, and a second exhaust line for transporting oxygen-side reaction products from the electrolysis device; and the second evaporator comprises a first sub-evaporator connected on the first exhaust line and / or a second sub-evaporator connected on the second exhaust line.

[0013] In some embodiments, the second evaporator comprises the first sub-evaporator and the second sub-evaporator; the second branch comprises a main section and first and second branch sections connected in parallel on the main section; and the first sub-evaporator is connected on the first branch section, the second sub-evaporator is connected on the second branch section, and the second condenser and the second expansion valve are connected on the main section.

[0014] In some embodiments, the thermal management subsystem further comprises a flow regulating device that is controllable to regulate a ratio of refrigerant flowing through the first branch section to refrigerant flowing through the second branch section.

[0015] In some embodiments, the second evaporator comprises the first sub-evaporator and the second sub-evaporator, which are connected in series on the second branch, wherein: when the second branch is tapped into the main loop, the refrigerant circulates in the order of sequentially passing through the compressor, the second condenser, the second expansion valve, the first sub-evaporator, and the second sub-evaporator; or when the second branch is tapped into the main loop, the refrigerant circulates in the order of sequentially passing through the compressor, the second condenser, the second expansion valve, the second sub-evaporator, and the first sub-evaporator.

[0016] In some embodiments, the electrolysis system further comprises a hydrogen gas side primary gas-liquid separator for receiving and separating hydrogen gas side reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, a hydrogen gas side secondary gas-liquid separator disposed downstream of the hydrogen gas side primary gas-liquid separator, an oxygen gas side primary gas-liquid separator for receiving and separating oxygen gas side reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, and an oxygen gas side secondary gas-liquid separator disposed downstream of the oxygen gas side primary gas-liquid separator, wherein: the first exhaust line comprises a first section for transporting hydrogen gas side reaction products from the hydrogen gas side primary gas-liquid separator to the hydrogen gas side secondary gas-liquid separator, and the first sub-evaporator is for connection on the first section of the first exhaust line; and / or the second exhaust line comprises a first section for transporting oxygen gas side reaction products from the oxygen gas side primary gas-liquid separator to the oxygen gas side secondary gas-liquid separator, and the second sub-evaporator is for connection on the first section of the second exhaust line.

[0017] In another aspect, the present application provides an electrolysis system. The electrolysis system comprises: an electrolysis device for electrolyzing water in an electrolyte; a supply line for transporting electrolyte to the electrolysis device; an exhaust line for transporting reaction products from the electrolysis device; and a heat management subsystem as previously described, the condenser being a first condenser and connected on the supply line, and the evaporator being a second evaporator and connected on the exhaust line.

[0018] These techniques can be used alone or in any suitable combination. The foregoing summary is provided in illustrative rather than limiting terms. BRIEF DESCRIPTION OF DRAWINGS

[0019] The above and other aspects of the present application will become more apparent by a more detailed description of a preferred embodiment, taken in conjunction with the accompanying drawings. It should be understood, however, that the drawings solely provide illustrations of aspects of the present application and do not limit the scope of the application. Like reference numerals refer to like elements throughout the drawings. Additionally, for the purpose of brevity, not all components or parts of an electrolysis system and its heat management subsystem according to the present application are shown or labeled in the drawings. It is understood that the dimensions, proportions and number of components in the drawings are not intended to limit the scope of the present application. In the drawings:

[0020] Figure 1 is a schematic layout of an electrolysis system including a heat management subsystem according to some embodiments of the present application;

[0021] Figure 2 is a schematic layout of an electrolysis system including a heat management subsystem according to some embodiments of the present application; Figure 1A similar schematic layout, but showing the electrolysis system in an initial start-up state, and the thermal management subsystem in a heating mode; and

[0022] Figure 3 is similar to Figure 1 A similar schematic layout, but showing the electrolysis system in a normal operating state, and the thermal management subsystem in a cooling mode.

[0023] In Figure 1 , the pipes are represented by solid lines, and in Figure 2 and Figure 3 , the pipes in which fluid flow occurs are represented by solid lines, and the direction of fluid flow is represented by arrows on the solid lines, while the pipes in which no fluid flow occurs are represented by dashed lines. DETAILED DESCRIPTION

[0024] Some embodiments of the present application are described in detail below with reference to the accompanying drawings. In the following embodiments, in order to facilitate the description of the electrolysis system and the thermal management subsystem thereof according to the present application, an alkaline solution electrolysis system and a thermal management subsystem thereof are taken as examples. It should be understood that such examples do not mean any limitation on the present application, and the thermal management subsystem according to the present application can be used in other types of electrolysis systems, such as a proton exchange membrane (PEM) electrolysis system, an anion exchange membrane (AEM) electrolysis system, a solid oxide electrolysis system, etc. In addition, the features in each embodiment of the present application can be combined with each other without conflict.

[0025] Figure 1 An electrolysis system 10 according to some embodiments of the present application is shown. The electrolysis system 10 is an alkaline solution electrolysis system, which uses an alkaline solution (e.g., a potassium hydroxide solution, a sodium hydroxide solution, etc.) as an electrolyte. As shown in Figure 1 , the electrolysis system 10 includes an electrolysis device 11 configured for electrolyzing water in the electrolyte to generate hydrogen and oxygen. Specifically, the electrolysis device 11 generally includes a housing and a plurality of single electrolytic cells 11d contained in the housing, wherein each single electrolytic cell 11d includes cathode and anode plates spaced apart from each other, a cathode electrode in contact with the cathode plate, an anode electrode in contact with the anode plate, and a separator between the cathode electrode and the anode electrode, wherein the cathode and anode plates can be electrically connected with an external direct current power source (not shown) and together with the cathode and anode electrodes are immersed in the electrolyte, while the separator is also immersed in the electrolyte and allows ions to pass through but prohibits gas molecules to pass through.

[0026] As an example, consider a single electrolytic cell 1 Id. During operation, electrolyte will be circulated through the single electrolytic cell 1 Id, and an external DC power source (not shown) will supply DC power to its cathode and anode plates. At the cathode electrode, water molecules are reduced to hydrogen molecules and hydroxide ions (i.e., a reduction reaction occurs: 4H2O + 4e - → 2H 2 + 4OH - ), where the hydrogen molecules are expelled with the electrolyte as they cannot pass through the separator, and the hydroxide ions pass from the cathode electrode to the anode electrode driven by the voltage. At the anode electrode, the hydroxide ions are oxidized to oxygen molecules and water molecules (i.e., an oxidation reaction occurs: 4OH - → 2H2O + O 2 + 4e - ), where the oxygen molecules are expelled with the electrolyte as they cannot pass through the separator.

[0027] By the same principle, each single electrolytic cell 1 Id can receive electrolyte and expel hydrogen-containing electrolyte at the cathode side (i.e., expel cathode side reaction products and unspent electrolyte) and oxygen-containing electrolyte at the anode side (i.e., expel anode side reaction products and unspent electrolyte) after the above electrochemical reactions. To this end, the electrolysis device 1 1 is provided with a hydrogen side (also referred to as cathode side) outlet 1 1 a for expelling hydrogen-containing electrolyte, an oxygen side (also referred to as anode side) outlet 1 1 b for expelling oxygen-containing electrolyte, and an inlet 1 1 c for receiving electrolyte. The electrolysis device 1 1 is also internally provided with a plurality of sets of flow channels (also referred to as manifolds) that can distribute electrolyte received through the inlet 1 1 c to each single electrolytic cell 1 Id, collect hydrogen-containing electrolyte expelled by each single electrolytic cell 1 Id at the hydrogen side outlet 1 1 a, and collect oxygen-containing electrolyte expelled by each single electrolytic cell 1 Id at the oxygen side outlet 1 1 b. In addition, as a byproduct of hydrogen and oxygen, heat will also be generated during the above electrochemical reactions along with hydrogen and oxygen, which will be absorbed by the electrolyte and expelled from the electrolysis device 1 1 along with the electrolyte to avoid overheating of the electrolysis device 1 1 during operation, which of course also results in a higher temperature of the electrolyte at the hydrogen side outlet 1 1 a and the oxygen side outlet 1 1 b than at the inlet 1 1 c.

[0028] Please continue to refer to Figure 1electrolysis device 11 and the primary gas-liquid separator 12. Due to the presence of this portion of the circulation line 13, electrolyte can be circulated between the electrolysis device 11 and the primary gas-liquid separator 12. That is, electrolyte can be circulated to flow through the electrolysis device 11 and the primary gas-liquid separator 12. In this configuration, the primary gas-liquid separator 12 can supply electrolyte to the electrolysis device 11 through the circulation line 13 to enable the electrolysis device 11 to utilize the electrolyte and generate hydrogen and oxygen through the electrochemical reactions described previously, while the electrolysis device 11 can discharge electrolyte containing hydrogen and oxygen (i.e., reaction products and unspent electrolyte) into the primary gas-liquid separator 12 through the circulation line 13 so that the electrolyte can be stored in the primary gas-liquid separator 12 and the hydrogen and oxygen can be separated from the electrolyte in the primary gas-liquid separator 12. That is, the primary gas-liquid separator 12 can also be used for gas-liquid separation to separate the hydrogen and oxygen from the electrolyte. As will be described in detail below, the circulation line 13 can include a supply line for transporting electrolyte from the primary gas-liquid separator 12 to the electrolysis device 11 and a discharge line for transporting reaction products and unspent electrolyte from the electrolysis device 11. Furthermore, as will be described in detail below, the electrolysis system 10 can also include a secondary gas-liquid separator 15 connected downstream of the primary gas-liquid separator 12 for further gas-liquid separation of the reaction products separated by the primary gas-liquid separator 12 to improve the purity thereof.

[0029] As Figure 1As shown, the primary gas-liquid separator 12 can include a hydrogen-side primary gas-liquid separator 12a for storing electrolyte and receiving and separating the hydrogen-side reaction products and unspent electrolyte from the electrolysis device 11, and an oxygen-side primary gas-liquid separator 12b for storing electrolyte and receiving and separating the oxygen-side reaction products and unspent electrolyte from the electrolysis device 11. The secondary gas-liquid separator 15 can include a hydrogen-side secondary gas-liquid separator 15a disposed downstream of the hydrogen-side primary gas-liquid separator 12a, and an oxygen-side secondary gas-liquid separator 15b disposed downstream of the oxygen-side primary gas-liquid separator 12b. Accordingly, the discharge line of the circulation line 13 can include a first (hydrogen-side) discharge line 13a for transporting the hydrogen-side reaction products and unspent electrolyte from the electrolysis device 11, and a second (oxygen-side) discharge line 13b for transporting the oxygen-side reaction products and unspent electrolyte from the electrolysis device 11. In particular, the first discharge line 13a can include a first section 13al and a second section 13a2. The first section 13al of the first discharge line 13a fluidly communicates the hydrogen-side outlet 11a of the electrolysis device 11 with an inlet 12al of the hydrogen-side primary gas-liquid separator 12a, and the second section 13a2 fluidly communicates a hydrogen outlet 12a3 of the hydrogen-side primary gas-liquid separator 12a with an inlet (not labeled) of the hydrogen-side secondary gas-liquid separator 15a. The second discharge line 13b can include a first section 13bl and a second section 13b2. The first section 13bl of the second discharge line 13b fluidly communicates the oxygen-side outlet 11b of the electrolysis device 11 with an inlet 12bl of the oxygen-side primary gas-liquid separator 12b, and the second section 13b2 fluidly communicates an oxygen outlet 12b3 of the oxygen-side primary gas-liquid separator 12b with an inlet (not labeled) of the oxygen-side secondary gas-liquid separator 15b.

[0030] Further, the first section 13cl of the supply line 13c fluidly communicates an electrolyte outlet 12a2 of the hydrogen-side primary gas-liquid separator 12a and an electrolyte outlet 12b2 of the oxygen-side primary gas-liquid separator 12b with the inlet 11c of the electrolysis device 11. That is, the outlet 12a2 of the hydrogen-side primary gas-liquid separator 12a and the outlet 12b2 of the oxygen-side primary gas-liquid separator 12b can be in fluid communication with each other and supply electrolyte to the inlet 11c of the electrolysis device 11 through the same first section 13cl. To this end, as Figure 1 shown, the electrolysis system 10 further includes an electrolyte pump 14 disposed on the first section 13cl, which can drive the electrolyte in the first section 13cl to flow along a direction from the hydrogen-side primary gas-liquid separator 12a and the oxygen-side primary gas-liquid separator 12b to the electrolysis device 11, thereby transporting the electrolyte in the hydrogen-side primary gas-liquid separator 12a and the oxygen-side primary gas-liquid separator 12b into the electrolysis device 11. In particular, asFigure 1 As shown, the inlet 12a1 and the electrolyte outlet 12a2 of the hydrogen side primary gas-liquid separator 12a are disposed at the top and the bottom thereof, respectively, and the inlet 12b1 and the electrolyte outlet 12b2 of the oxygen side primary gas-liquid separator 12b are also disposed at the top and the bottom, respectively. In addition, the hydrogen outlet 12a3 of the hydrogen side primary gas-liquid separator 12a is also disposed at the top thereof, and the oxygen outlet 12b3 of the oxygen side primary gas-liquid separator 12b is also disposed at the top thereof, thereby for allowing the separated hydrogen and oxygen to be delivered downstream for secondary gas-liquid separation and storage.

[0031] In addition, as shown, Figure 1 The hydrogen storage device 16a and the oxygen storage device 16b can be connected downstream of the hydrogen side secondary gas-liquid separator 15a and the oxygen side secondary gas-liquid separator 15b, respectively, for receiving the hydrogen from the hydrogen side secondary gas-liquid separator 15a and the oxygen from the oxygen side secondary gas-liquid separator 15b, respectively.

[0032] In the above configuration, the electrolytes from the hydrogen-side primary gas-liquid separator 12a and the oxygen-side primary gas-liquid separator 12b can be transported to the electrolysis unit 11 through the first section 13c1 of the supply pipeline 13c. The electrolysis unit 11 can use these electrolytes to generate hydrogen and oxygen through electrochemical reactions and discharge electrolytes containing hydrogen (i.e., hydrogen-side reaction products and unconsumed electrolytes) and electrolytes containing oxygen (i.e., oxygen-side reaction products and unconsumed electrolytes). The hydrogen-containing electrolytes from the electrolysis unit 11 can be transported to the hydrogen-side primary gas-liquid separator 12a through the first discharge pipeline 13a, where hydrogen and electrolytes are separated and the electrolytes are stored. The oxygen-containing electrolytes from the electrolysis unit 11 can be transported to the oxygen-side primary gas-liquid separator 12b through the second discharge pipeline 13b, where oxygen and electrolytes are separated and the electrolytes are stored. The gas separated by the hydrogen-side primary gas-liquid separator 12a is typically a mixture of hydrogen and gaseous water. As will be described in detail below, the mixed gas can be cooled before entering the hydrogen-side secondary gas-liquid separator 15a to condense the gaseous water into liquid water. This allows the liquid water to be separated from the hydrogen in the hydrogen-side secondary gas-liquid separator 15a, thereby improving the purity of the hydrogen. The hydrogen can then be transported from the hydrogen-side secondary gas-liquid separator 15a to the hydrogen storage device 16a. Similarly, the gas separated by the oxygen-side primary gas-liquid separator 12b is typically a mixture of oxygen and gaseous water. As will be described in detail below, the mixed gas can be cooled before entering the oxygen-side secondary gas-liquid separator 15b to condense the gaseous water into liquid water. This allows the liquid water to be separated from the oxygen in the oxygen-side secondary gas-liquid separator 15b, thereby improving the purity of the oxygen. Subsequently, hydrogen can be transported from the oxygen-side secondary gas-liquid separator 15b to the oxygen storage device 16b. Although not shown in the figure, it is conceivable that the water separated by the hydrogen-side secondary gas-liquid separator 15a and the oxygen-side secondary gas-liquid separator 15b can be transported, for example, to the hydrogen-side primary gas-liquid separator 12a and the oxygen-side primary gas-liquid separator 12b, respectively, and thus recycled back to the electrolysis unit 11.

[0033] The water in the electrolyte is consumed during electrolysis. For example... Figure 1 As shown, the electrolysis system 10 may also include a water source 17 (or referred to as a "water replenishment device") for replenishing water to the electrolysis system 10, thereby maintaining the electrolyte concentration in the electrolysis system 10 at an appropriate level. Accordingly, a second section 13c2 of the supply line 13c may be used to transport water from the water source 17 to a primary gas-liquid separator (e.g., an oxygen-side primary gas-liquid separator 12b).

[0034] As previously mentioned, in the case where, for example, the electrolysis system 10 is in a start-up phase, it is necessary to heat the electrolyte to be fed to the electrolysis device 11 in order to rapidly increase the temperature in the electrolysis device 11 to a range suitable for carrying out the electrolysis reaction. Moreover, in the case where the electrolysis system 10 is in normal operation, it is necessary to cool the reaction product in order to promote its separation from the electrolyte, in particular from the water contained in the electrolyte.

[0035] To this end, the electrolysis system 10 comprises a thermal management subsystem 100 configured to be able to operate in a heating mode, as illustrated in Figure 2 , in the case where, for example, the electrolysis system 10 is in a start-up phase, in order to heat the electrolyte to be fed to the electrolysis device 11, and to be able to operate in a cooling mode, as illustrated in Figure 3 , in the case where the electrolysis system 10 is in normal operation, in order to cool the reaction product.

[0036] As will be described in detail hereinafter, the thermal management subsystem 100 is configured to be able to switch between a heating loop, as illustrated in Figure 2 , and a cooling loop, as illustrated in Figure 3 . In other words, the thermal management subsystem 100 is able to be selectively placed in the heating loop, as illustrated in Figure 2 , or in the cooling loop, as illustrated in Figure 3 . The thermal management subsystem 100 is in the heating mode when switched to the heating loop, as illustrated in Figure 2 , and is in the cooling mode when switched to the cooling loop, as illustrated in Figure 3 . As illustrated in Figure 1 and Figure 2 , the heating loop comprises a compressor 105 and a first condenser 111. The first condenser 111 is connected on the feed line 13c and the compressor 105 is used to drive the circulation of a refrigerant along the heating loop so that the refrigerant releases heat when flowing through the first condenser 111 to heat the electrolyte transported via the feed line 13c. That is, the heating loop is configured so that the refrigerant releases heat when flowing through the first condenser 111 to heat the electrolyte transported via the feed line 13c. As illustrated in Figure 1 and Figure 3 , the cooling loop comprises the same compressor 105 and a second evaporator 123. The second evaporator 123 is connected on the discharge line and the compressor 105 is used to drive the circulation of the refrigerant along the cooling loop so that the refrigerant absorbs heat when flowing through the second evaporator 123 to cool the reaction product transported via the discharge line. That is, the heating loop is configured so that the refrigerant absorbs heat when flowing through the second evaporator 123 to cool the reaction product transported via the discharge line. As used in the present application, the term “refrigerant” refers to a working substance that is constantly circulated in the loop and that, by virtue of its own state change, achieves heat transfer. The refrigerant is able to absorb heat in the evaporator to vaporize and is able to be cooled in the condenser to liquefy.

[0037] With this configuration, the thermal management subsystem 100 can (i) switch to the heating loop when heating of the electrolyte to be supplied to the electrolysis unit 11 is required (e.g., during the start-up phase of the electrolysis system 10), using the compressor 105 to drive the refrigerant to heat the electrolyte, and (ii) use the same compressor 105 to drive the refrigerant to cool the reaction products during normal operation of the electrolysis system 100. Compared to the electric heaters and semiconductor coolers used in conventional electrolysis systems, this configuration of the thermal management subsystem 100 provides higher heating and cooling efficiency, significantly reducing energy consumption and thus improving the energy utilization efficiency of the electrolysis system 10.

[0038] like Figures 1 to 3 As shown, the thermal management subsystem 100 includes a refrigerant circulation line 130 and a line switching mechanism 140. The refrigerant circulation line 130 includes a main line 133 and a first branch line 131 and a second branch line 132 connected in parallel to the main line 133. The main line 133 may include a first node N1 and a second node N2 that are separate from each other. The first branch line 131 and the second branch line 132 may be connected in parallel between the first node N1 and the second node N2. A compressor 105 is connected to the main line 133, a first condenser 111 is connected to the first branch line 131, and a second evaporator 123 is connected to the second branch line 132. That is, the first condenser 111 is connected to both the supply line 13c and the first branch line 131 of the refrigerant circulation line 130 to achieve heat exchange between the electrolyte and the refrigerant. The second evaporator 123 is connected to both the discharge line and the second branch line 132 of the refrigerant circulation line 130 to achieve heat exchange at least between the reaction products and the refrigerant. This will be described in detail below.

[0039] The pipeline switching mechanism 140 is configured to selectively connect either the first branch 131 or the second branch 132 to the main line 133. For example... Figure 2 As shown, when the first branch 131 is connected to the main line 133, the thermal management subsystem 100 is switched to a heating loop (or, switched to heating mode). In this case, the compressor 105 can drive refrigerant from the main line 133 into the first branch 131 to flow through the first condenser 111, thereby heating the electrolyte supplied via the supply line 13c. Subsequently, the refrigerant can return from the first branch 131 to the main line 133 to return to the compressor 105. Figure 3As shown, when the second branch 132 is connected to the main branch 133, the thermal management subsystem 100 is switched to a cooling loop (or, switched to cooling mode). In this case, the compressor 105 can drive the refrigerant from the main branch 133 into the second branch 132 to flow through the second evaporator 123, thereby cooling the reaction products transported via the discharge line. Subsequently, the refrigerant can return from the second branch 132 to the main branch 133 to return to the compressor 105. Regardless of whether the thermal management subsystem 100 is in a heating loop or a cooling loop, the compressor 105 drives the refrigerant to flow in the same direction in the main branch 133.

[0040] In some embodiments, such as Figure 2 and Figure 3 As shown, the pipeline switching mechanism 140 may include a first three-way valve 141 disposed at the first node N1 and a second three-way valve 142 disposed at the second node N2. The first three-way valve 141 and the second three-way valve 142 may cooperate to selectively connect the first branch 131 or the second branch 132 to the main line 133. It should be understood that the specific form of the pipeline switching mechanism 140 is not limited to this. For example, in other embodiments, the pipeline switching mechanism 140 may include only the first three-way valve 141 disposed at the first node N1 or the second three-way valve 142 disposed at the second node N2. As another example, in other embodiments, the pipeline switching mechanism 140 may include an on / off valve disposed on the first branch 131 and an on / off valve disposed on the second branch 132, which may cooperate to selectively connect the first branch 131 or the second branch 132 to the main line 133.

[0041] like Figures 1 to 3 As shown, the thermal management subsystem 100 also includes a first expansion valve 112 and a first evaporator 113. Both the first expansion valve 112 and the first evaporator 113 are connected to the first branch 131 of the refrigerant circulation line 130. Figure 2 As shown, when the thermal management subsystem 100 is switched to the heating loop (or, switched to heating mode), the first branch 131 is connected to the main branch 133, and the refrigerant passes through the compressor 105, the first condenser 111, the first expansion valve 112, and the first evaporator 113 in that order (e.g., ...). Figure 2In this case, the refrigerant is vaporized in the first evaporator 113 by absorbing heat from a heat source (not shown, but it is contemplated that it can be any suitable heat source). Subsequently, the refrigerant is compressed into a high-pressure high-temperature gas by the compressor 105. Subsequently, the refrigerant is liquefied in the first condenser 111 by being cooled by the electrolyte delivered via the feed line 13c, while the electrolyte is heated by the refrigerant. Subsequently, the liquid refrigerant is depressurized by the first expansion valve 112 and enters the first evaporator 113 again. By means of this circulation of the refrigerant, heating of the electrolyte delivered via the feed line 13c can be achieved. It is contemplated that the configuration of the heating loop of the present application is not limited to this, but can have any suitable configuration such that the refrigerant releases heat when flowing through the first condenser 111 to heat the electrolyte delivered via the feed line 13c.

[0042] In some embodiments, as shown in FIG. 1, the first condenser 111 can be connected on the first section 13cl of the feed line 13c. With this configuration, when the thermal management subsystem 100 is in the heating mode, the first condenser 111 can heat both the electrolyte from the hydrogen-side primary gas-liquid separator 12a and the electrolyte from the oxygen-side primary gas-liquid separator 12b, which can include water replenished from the water source 17. Figures 1 to 3

[0043] It is understood that the location of the first condenser 111 is not limited to this. In other embodiments, the first condenser 111 can be connected on the second section 13c2 of the feed line 13c. With this configuration, when the thermal management subsystem 100 is in the heating mode, the first condenser 111 can heat the water replenished from the water source 17. The water is mixed with the electrolyte after entering the primary gas-liquid separator (e.g., the oxygen-side primary gas-liquid separator 12b) to achieve heating of the electrolyte to be fed to the electrolyzer 11. In addition, in other embodiments, the first condenser 111 can be configured to heat either the electrolyte from the hydrogen-side primary gas-liquid separator 12a or the electrolyte from the oxygen-side primary gas-liquid separator 12b, which can include water replenished from the water source 17, separately. In addition, in other embodiments, the water source 17 can be connected directly to the inlet 11c of the electrolyzer via the feed line 13c, and the first condenser 111 can be configured to heat the water replenished from the water source 17.

[0044] As shown in FIG. 1, the thermal management subsystem 100 further includes a second condenser 121 and a second expansion valve 122. The second condenser 121 and the second expansion valve 122 are both connected on the second branch 132. As shown in FIG. 1, the second condenser 121 and the second expansion valve 122 are connected in series on the second branch 132. With this configuration, when the thermal management subsystem 100 is in the heating mode, the second condenser 121 can heat the electrolyte delivered via the feed line 13c, while the second expansion valve 122 can depressurize the electrolyte. Figures 1 to 3 Figure 3 ​​As shown, when the thermal management subsystem 100 is switched to the cooling loop (or, in other words, to the cooling mode), the second branch 132 is accessed to the main loop 133, and the refrigerant circulates in the main loop 133 and the second branch 132 in the order of passing through the compressor 105, the second condenser 121, the second expansion valve 122 and the second evaporator 123 (as indicated by the arrows in Figure 3 In this case, the refrigerant vaporizes in the second evaporator 123 by absorbing heat from the heat source, i.e., the reaction products delivered via the exhaust line, while the reaction products are cooled by the refrigerant. Subsequently, the refrigerant is compressed into a high-pressure and high-temperature gas by the compressor 105. Subsequently, the refrigerant is liquefied in the second condenser 121 by the cold source (not shown, but it can be envisaged that it can be any suitable cold source). Subsequently, the refrigerant in liquid state is depressurized by the second expansion valve 122 and enters the second evaporator 123 again. By means of this circulation of the refrigerant, the cooling of the reaction products delivered via the exhaust line can be achieved. It can be envisaged that the configuration of the cooling loop of the present application is not limited thereto, but can have any suitable configuration such that the refrigerant absorbs heat when flowing through the second evaporator 123 to cool the reaction products delivered via the exhaust line.

[0045] In some embodiments, as shown in Figures 1 to 3 The second evaporator 123 can include a first (hydrogen side) sub-evaporator 123a connected to the first exhaust line 13a and a second (oxygen side) sub-evaporator 123b connected to the second exhaust line 13b. By this configuration, the hydrogen side reaction products and the oxygen side reaction products can be cooled separately.

[0046] In one of these embodiments, as shown in Figures 1 to 3 The first sub-evaporator 123a and the second sub-evaporator 123b can be connected in parallel to the second branch 132. Specifically, the second branch 132 can include a main section 132c and a first branch section 132a and a second branch section 132b connected in parallel to the main section 132c. Specifically, the main section 132c can include a third node N3 and a fourth node N4 separated from each other. The first branch section 132a and the second branch section 132b can be connected in parallel between the third node N3 and the fourth node N4. The first sub-evaporator 123a is connected to the first branch section 132a, the second sub-evaporator 123b is connected to the second branch section 132b, and the second condenser 121 and the second expansion valve 122 are connected to the main section 132c. In this way, the first sub-evaporator 123a is connected to the first exhaust line 13a and the first branch section 132a to achieve heat exchange between the hydrogen side reaction products and the refrigerant. The second sub-evaporator 123b is connected to the second exhaust line 13b and the second branch section 132b to achieve heat exchange between the oxygen side reaction products and the refrigerant.

[0047] Please continue to refer to Figures 1 to 3 , the thermal management subsystem 100 can optionally include a flow regulating device 150, which is controllable to regulate the proportion of refrigerant flowing through the first branch section 132a and the refrigerant flowing through the second branch section 132b. With this configuration, the cooling of the hydrogen-side reaction product and the oxygen-side reaction product can be precisely regulated. As shown, the flow regulating device 150 can be a three-way regulating valve disposed at the third node N3. It should be understood that the specific form of the flow regulating device 150 is not limited thereto. For example, in other embodiments, the flow regulating device 150 can also be a three-way regulating valve disposed at the fourth node N4. As another example, the flow regulating device can include two regulating valves disposed on the first branch section 132a and the second branch section 132b, respectively, which can cooperate to regulate the proportion of refrigerant flowing through the first branch section 132a and the refrigerant flowing through the second branch section 132b.

[0048] In the case where the second evaporator 123 includes a first sub-evaporator 123a and a second sub-evaporator 123b, although not shown in the figure, it is conceivable that in other embodiments, the first sub-evaporator 123a and the second sub-evaporator 123b can be connected in series on the second branch 132. For example, the first sub-evaporator 123a can be upstream of the second sub-evaporator 123b in the refrigerant flow path, such that when the second branch 132 is tapped into the main branch 133, the refrigerant circulates in the cooling loop in the order of passing through the compressor 105, the second condenser 121, the second expansion valve 122, the first sub-evaporator 123a, and the second sub-evaporator 123b. As another example, the first sub-evaporator 123a can be downstream of the second sub-evaporator 123b in the refrigerant flow path, such that when the second branch 132 is tapped into the main branch 133, the refrigerant circulates in the cooling loop in the order of passing through the compressor 105, the second condenser 121, the second expansion valve 122, the second sub-evaporator 123b, and the first sub-evaporator 123a.

[0049] In some embodiments, as Figures 1 to 3 shown, the first sub-evaporator 123a can be connected on the second section 13a2 of the first discharge line 13a to cool the gas separated out by the hydrogen-side primary gas-liquid separator 12a, so that the gaseous water condenses into liquid water. This enables the liquid water to be subsequently separated from the hydrogen gas in the hydrogen-side secondary gas-liquid separator 15a, thereby improving the purity of the hydrogen gas.

[0050] Although not shown, it is conceivable that in other partial embodiments, the first sub-evaporator 123a can be connected on the first section 13al of the first discharge line 13a to cool the hydrogen-side reaction products and the unspent electrolyte conveyed from the electrolyzer 11 via the first section 13al towards the hydrogen-side primary gas-liquid separator 12a. That is, in this case, the refrigerant cools both the hydrogen-side reaction products and the unspent electrolyte in the first sub-evaporator 123a.

[0051] In some embodiments, as shown in FIG. 1, the second sub-evaporator 123b can be connected on the second section 13b2 of the second discharge line 13b to cool the gas separated out by the oxygen-side primary gas-liquid separator 12b so that the gaseous water condenses into liquid water. This enables the liquid water to be subsequently separated from the oxygen in the oxygen-side secondary gas-liquid separator 15b, thereby improving the purity of the oxygen. Figures 1 to 3

[0052] Although not shown, it is conceivable that in other partial embodiments, the second sub-evaporator 123b can be connected on the first section 13bl of the second discharge line 13b to cool the oxygen-side reaction products and the unspent electrolyte conveyed from the electrolyzer 11 via the first section 13bl towards the oxygen-side primary gas-liquid separator 12b. That is, in this case, the refrigerant cools both the oxygen-side reaction products and the unspent electrolyte in the second sub-evaporator 123b.

[0053] Although the configuration of the cooling loop is described above in connection with the example in which the second evaporator 123 comprises the first sub-evaporator 123a and the second sub-evaporator 123b, it is understood that in other partial embodiments, the cooling loop can comprise only one of the first sub-evaporator 123a and the second sub-evaporator 123b, or can comprise additional evaporators. The additional evaporators can be connected in the cooling loop in any suitable relationship, such as in series or in parallel, with the first sub-evaporator 123a and the second sub-evaporator 123b.

[0054] Although not shown in the figures, it is understood that the thermal management subsystem can comprise one or more sensors which can be arranged on any one or any combination of the aforementioned sections of the feed lines and the discharge lines to measure the temperature of the fluids flowing therethrough. The operation of the thermal management subsystem 100, i.e. the control of the heating mode and the cooling mode, can be precisely controlled based on the measured temperatures.

[0055] ​It should also be understood that, although the above describes switching to the heating mode of the thermal management subsystem 100 when the electrolysis system 10 is in a start-up phase, and switching to the cooling mode of the thermal management subsystem 100 when the electrolysis system 10 is in a normal operation, it should be understood that the operation of the thermal management subsystem 100 is not limited thereto. Accordingly, the heating mode and the cooling mode of the thermal management subsystem 100 can be enabled as needed under any suitable scenario.

[0056] In this application, the terms "first", "second" and the like are used only to distinguish one component, line or mode from another, but the components, lines and modes should not be limited by such terms.

[0057] The present application has been described in detail above with specific reference to particular embodiments. It is clear, however, to a person skilled in the art that variations or modifications of such embodiments can be made without departing from the spirit of the present application, and that such variations or modifications are within the scope of the present application.

Claims

1. A thermal management subsystem (100) for an electrolysis system (10), characterized by, The electrolysis system comprises an electrolysis device (11) for electrolyzing water in an electrolyte, a feed line (13c) for delivering electrolyte to the electrolysis device, and a discharge line for delivering reaction products from the electrolysis device, the thermal management subsystem being configured to switch between a heating loop and a cooling loop, wherein: the heating loop comprises a compressor (105) and a condenser (111) for connection to the feed line, and the compressor is configured to drive circulation of a refrigerant along the heating loop such that the refrigerant releases heat when flowing through the condenser to heat electrolyte delivered via the feed line; and the cooling loop comprises the compressor (105) and an evaporator (123) for connection to the discharge line, and the compressor is configured to drive circulation of a refrigerant along the cooling loop such that the refrigerant absorbs heat when flowing through the evaporator to cool reaction products delivered via the discharge line.

2. The thermal management subsystem of claim 1, wherein, The thermal management subsystem further comprises: a refrigerant circulation line (130) comprising a main leg (133) and first and second branch legs (131, 132) connected in parallel to the main leg, the compressor being connected to the main leg, the condenser being connected to the first branch leg, and the evaporator being connected to the second branch leg; and a line switching mechanism (140) configured to selectively access the first or second branch leg to the main leg; wherein the thermal management subsystem is switched to the heating loop when the first branch leg is accessed to the main leg, and the thermal management subsystem is switched to the cooling loop when the second branch leg is accessed to the main leg.

3. The thermal management subsystem of claim 2, wherein: the condenser is a first condenser, and the evaporator is a second evaporator; the thermal management subsystem further comprises a first expansion valve (112) and a first evaporator (113), both connected to the first branch leg; and when the first branch leg is accessed to the main leg, the refrigerant circulates in the main leg and the first branch leg in the order of passing through the compressor, the first condenser, the first expansion valve, and the first evaporator in sequence.

4. The thermal management subsystem of claim 3, wherein: the electrolysis system further comprises a primary gas-liquid separator (12) for receiving and separating reaction products and unconsumed electrolyte from the electrolysis device and storing electrolyte, the feed line comprises a first section (13c1) for delivering electrolyte from the primary gas-liquid separator to the electrolysis device, and the first condenser is connected to the first section of the feed line; or ​ The electrolysis system further comprises a primary gas-liquid separator (12) for receiving and separating reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, the feed line comprising a second section for transporting water from a water source to the primary gas-liquid separator or the electrolysis device, the first condenser being for connection on the second section (13c2) of the feed line.

5. The thermal management subsystem of any one of claims 2 to 4, wherein: the condenser is a first condenser and the evaporator is a second evaporator; the thermal management subsystem further comprises a second condenser (121) and a second expansion valve (122), both connected on the second branch; and when the second branch is tapped into the main loop, the refrigerant circulates in the main loop and the second branch in the order of the compressor, the second condenser, the second expansion valve, and the second evaporator.

6. The thermal management subsystem of claim 5, wherein: the exhaust line comprises a first exhaust line (13a) for transporting hydrogen-side reaction products from the electrolysis device, and a second exhaust line (13b) for transporting oxygen-side reaction products from the electrolysis device; and the second evaporator comprises a first sub-evaporator (123a) connected on the first exhaust line and / or a second sub-evaporator (123b) connected on the second exhaust line.

7. The thermal management subsystem of claim 6, wherein: the second evaporator comprises the first sub-evaporator and the second sub-evaporator; the second branch comprises a main section (132c) and first and second branch sections (132a, 132b) connected in parallel on the main section; and the first sub-evaporator is connected on the first branch section, the second sub-evaporator is connected on the second branch section, and the second condenser and the second expansion valve are connected on the main section.

8. The thermal management subsystem of claim 7, wherein, the thermal management subsystem further comprises a flow regulating device (150) controllable to regulate the proportion of refrigerant flowing through the first branch section to refrigerant flowing through the second branch section.

9. The thermal management subsystem of claim 6, wherein, the second evaporator comprises the first sub-evaporator and the second sub-evaporator, the first sub-evaporator and the second sub-evaporator being connected in series on the second branch, wherein: when the second branch is tapped into the main loop, the refrigerant circulates in the order of the compressor, the second condenser, the second expansion valve, the first sub-evaporator, and the second sub-evaporator; or when the second branch is tapped into the main loop, the refrigerant circulates in the order of the compressor, the second condenser, the second expansion valve, the second sub-evaporator, and the first sub-evaporator.

10. The thermal management subsystem of any one of claims 7 to 9, wherein, The electrolysis system further comprises a hydrogen side primary gas-liquid separator (12a) for receiving and separating hydrogen side reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, a hydrogen side secondary gas-liquid separator (15a) disposed downstream of the hydrogen side primary gas-liquid separator, an oxygen side primary gas-liquid separator (12b) for receiving and separating oxygen side reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, and an oxygen side secondary gas-liquid separator (15b) disposed downstream of the oxygen side primary gas-liquid separator, wherein: the first exhaust line comprises a first section (13a2) for transporting hydrogen side reaction products from the hydrogen side primary gas-liquid separator to the hydrogen side secondary gas-liquid separator, and the first sub-evaporator is for connection on the first section of the first exhaust line; and / or the second exhaust line comprises a first section (13b2) for transporting oxygen side reaction products from the oxygen side primary gas-liquid separator to the oxygen side secondary gas-liquid separator, and the second sub-evaporator is for connection on the first section of the second exhaust line.

11. An electrolysis system (10), characterized by The electrolysis system comprises: an electrolysis device (11) for electrolyzing water in an electrolyte; a supply line for transporting electrolyte to the electrolysis device; an exhaust line for transporting reaction products from the electrolysis device; and a heat management subsystem (100) according to any one of claims 1 to 10, the condenser being a first condenser and being connected on the supply line, and the evaporator being a second evaporator and being connected on the exhaust line. the electrolysis system further comprises a hydrogen side primary gas-liquid separator (12a) for receiving and separating hydrogen side reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, a hydrogen side secondary gas-liquid separator (15a) disposed downstream of the hydrogen side primary gas-liquid separator, an oxygen side primary gas-liquid separator (12b) for receiving and separating oxygen side reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, and an oxygen side secondary gas-liquid separator (15b) disposed downstream of the oxygen side primary gas-liquid separator, wherein: the first exhaust line comprises a first section (13a2) for transporting hydrogen side reaction products from the hydrogen side primary gas-liquid separator to the hydrogen side secondary gas-liquid separator, and the first sub-evaporator is for connection on the first section of the first exhaust line; and / or the second exhaust line comprises a first section (13b2) for transporting oxygen side reaction products from the oxygen side primary gas-liquid separator to the oxygen side secondary gas-liquid separator, and the second sub-evaporator is for connection on the first section of the second exhaust line. the electrolysis system further comprises a hydrogen side primary gas-liquid separator (12a) for receiving and separating hydrogen side reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, a hydrogen side secondary gas-liquid separator (15a) disposed downstream of the hydrogen side primary gas-liquid separator, an oxygen side primary gas-liquid separator (12b) for receiving and separating oxygen side reaction products and unspent electrolyte from the electrolysis device and storing electrolyte, and an oxygen side secondary gas-liquid separator (15b) disposed downstream of the oxygen side primary gas-liquid separator, wherein: the first exhaust line comprises a first section (13a2) for transporting hydrogen side reaction products from the hydrogen side primary gas-liquid separator to the hydrogen side secondary gas-liquid separator, and the first sub-evaporator is for connection on the first section of the first exhaust line; and / or the second exhaust line comprises a first section (13b2) for transporting oxygen side reaction products from the oxygen side primary gas-liquid separator to the oxygen side secondary gas-liquid separator, and the second sub-evaporator is for connection on the first section of the second exhaust line.

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