Gas recovery device of flow battery

Abstract

The utility model relates to a gas recovery device of a flow battery. The gas recovery device comprises a positive electrode pipeline, a negative electrode pipeline, a reaction chamber and an absorption chamber, the positive pipeline and the negative pipeline are communicated with the reaction chamber; the reaction chamber comprises a light source generator for promoting the first gas and the second gas to react; the absorption chamber comprises an electrolyte inlet, an electrolyte outlet, an absorption chamber air inlet hole and an absorption chamber air outlet hole, the absorption chamber air inlet hole is connected with the reaction chamber air outlet hole, and the electrolyte inlet of the absorption chamber and the absorption chamber air outlet hole are respectively connected with a positive storage tank of the flow battery. The first gas and the second gas react in the reaction chamber, are absorbed in the absorption chamber and flow back to the positive storage tank, so that the loss rate of chloride ions in the flow battery is slowed down, and the precipitation of electrolyte metal salt is reduced; relatively high energy density and energy conversion efficiency are maintained; the problem of supplementing chloride ions by adding chlorate-containing liquid is avoided, and the maintenance cost of the flow battery is reduced.

Description

Technical Field

[0001] This application relates to the field of flow batteries, and more specifically to a gas recovery device for a flow battery. Background Technology

[0002] In flow batteries, the electrolyte serves as the energy storage medium. The higher the concentration of metal compound solutes in the electrolyte, the greater the energy density of the flow battery. In conventional sulfuric acid electrolyte systems, the solubility of metal compound solutes is low, resulting in low energy density for the battery system. Furthermore, conventional sulfuric acid electrolyte systems have a narrow operating temperature range, requiring strict control of the system's operating temperature, which leads to lower system efficiency. Using chloric acid (such as hydrochloric acid or hypochlorous acid) as a single solvent, or adding chloride ions (such as sodium chloride or potassium chloride) to conventional sulfuric acid electrolytes to form a mixed acid system, can significantly improve the solubility of metal compound solutes and the operating temperature range, thereby increasing the energy density and energy conversion efficiency of the battery system.

[0003] However, when the electrolyte contains chloride ions, a chloride evolution side reaction occurs at the positive electrode and a hydrogen evolution side reaction occurs at the negative electrode during battery charging. The continuous occurrence of these side reactions gradually reduces the chloride and hydrogen ion content in the electrolyte, leading to the precipitation of metal salts (such as vanadium sulfate, VOSO4). The precipitation of metal salts causes a decrease in electrolyte concentration, thereby reducing energy density and energy conversion efficiency. To maintain a stable chloride ion concentration, chloric acid solution needs to be added to the electrolyte periodically, increasing maintenance costs. In current conventional battery systems, to mitigate chloride ion loss, the chlorine gas produced by the side reactions is usually directly introduced into the electrolyte for absorption. However, chlorine gas has very low solubility in acidic electrolytes, and bubbling cannot completely dissolve the precipitated chlorine gas into the electrolyte. Therefore, a gas recovery device capable of guiding the precipitated chlorine gas back into the electrolyte is urgently needed. Utility Model Content

[0004] The technical problem to be solved by this application is to provide a gas recovery device that can reduce the precipitation of metal salts due to chloride ion loss and effectively utilize the gas generated by the side reaction. This gas recovery device can reduce the maintenance cost of flow batteries and improve the energy density, energy conversion efficiency and safety of flow batteries.

[0005] The technical solution adopted in this application to solve the above-mentioned technical problems is a gas recovery device for a flow battery, comprising: a positive electrode pipeline and a negative electrode pipeline, wherein the first port of the positive electrode pipeline is connected to the positive electrode tank of the flow battery, and the first port of the negative electrode pipeline is connected to the negative electrode tank of the flow battery; a reaction chamber, comprising a light source generator and a reaction chamber outlet, wherein the positive electrode pipeline is connected to the reaction chamber for transmitting a first gas generated in the positive electrode tank to the interior of the reaction chamber, and the negative electrode pipeline is connected to the reaction chamber for transmitting a second gas generated in the negative electrode tank to the interior of the reaction chamber; the light source generator is used to generate a light source, which is used to promote the reaction between the first gas and the second gas; and an absorption chamber, wherein the top of the absorption chamber is provided with an electrolyte inlet, the bottom of the absorption chamber is provided with an electrolyte outlet, and the side wall of the absorption chamber is provided with an absorption chamber inlet and an absorption chamber outlet, wherein the absorption chamber inlet is connected to the reaction chamber outlet, and the electrolyte inlet and the absorption chamber outlet are respectively connected to the positive electrode tank of the flow battery.

[0006] In one embodiment of this application, the gas recovery device further includes a mixing chamber, and the positive electrode line and the negative electrode line are first connected to the mixing chamber and then connected to the reaction chamber, so that the first gas and the second gas are mixed in the mixing chamber before entering the reaction chamber.

[0007] In one embodiment of this application, the gas recovery device further includes a gas flow meter, which is disposed in the positive electrode pipeline and the negative electrode pipeline; the gas flow meter is used to control the first gas flow rate in the positive electrode pipeline to be greater than the second gas flow rate in the negative electrode pipeline.

[0008] In one embodiment of this application, the ratio of the first gas flow rate to the second gas flow rate is controlled to be 1:1-10:1.

[0009] In one embodiment of this application, the gas recovery device further includes a second gas detector, a first reflux pipeline and a second reflux pipeline, the mixing chamber includes a reflux hole, the second gas detector is connected to the gas outlet of the absorption chamber, the first reflux pipeline is connected to the positive electrode storage tank and the gas outlet of the absorption chamber, and the second reflux pipeline is connected to the gas outlet of the absorption chamber and the reflux hole.

[0010] The first return pipeline is configured to divert the gas discharged from the absorption chamber outlet to the positive electrode storage tank when the second gas detector does not detect the second gas.

[0011] The second return line is configured to guide the gas discharged from the absorption chamber outlet to the mixing chamber when the second gas detector detects the second gas.

[0012] In one embodiment of this application, the absorption chamber is provided with a material area, an air inlet area, and an air outlet area. The material area is filled with material, the air inlet of the absorption chamber is located in the air inlet area, and the air outlet of the absorption chamber is located in the air outlet area.

[0013] In one embodiment of this application, the height of the air inlet of the absorption chamber is lower than the height of the air outlet of the absorption chamber.

[0014] In one embodiment of this application, the gas recovery device further includes a pump device, which is disposed in the positive electrode line, the negative electrode line, the electrolyte inlet, and the electrolyte outlet.

[0015] In one embodiment of this application, the inner wall of the mixing chamber has two oppositely arranged side walls, and each side wall is provided with a plurality of baffles, which are staggered to form a gas flow channel.

[0016] In one embodiment of this application, the material includes any one or more of graphite spheres, graphite rings, and PP plastic spheres.

[0017] In one embodiment of this application, the wavelength of the light source generator in the reaction formula does not exceed 400 nanometers.

[0018] This application proposes a gas recovery device for a flow battery, in which the first and second gases generated by the side reaction react in the reaction chamber, are absorbed in the absorption chamber, and flow back to the positive electrode tank. This slows down the loss rate of chloride ions in the flow battery and reduces the precipitation of electrolyte metal salts; maintains high energy density and energy conversion efficiency; avoids the problem of adding large amounts of chloric acid solution to replenish chloride ions in practical applications, and reduces the maintenance cost of the flow battery. Attached Figure Description

[0019] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings, wherein:

[0020] Figure 1 This is a schematic diagram of a gas recovery device according to an embodiment of this application;

[0021] Figure 2 This is a schematic diagram of a gas recovery device according to another embodiment of this application.

[0022] Figure label:

[0023] Positive electrode line, 110; First port of positive electrode line, 111; Gas flow meter, 113; Negative electrode line, 120; First port of negative electrode line, 121; Reaction chamber, 130; Light source generator, 131; Gas outlet of reaction chamber, 132; Gas inlet of reaction chamber, 133; Absorption chamber, 140; Electrolyte inlet, 141; Electrolyte outlet, 142; Gas inlet of absorption chamber, 143; Gas outlet of absorption chamber, 144; Material area, 145; Gas inlet area, 146; Gas outlet area, 147; Filling material, 148; Mixing chamber, 150; Baffle, 151; Side wall, 152; Gas flow channel, 153; Return hole, 154; Pump device, 160; Second gas detector, 170; First return line, 180; Second return line, 190. Detailed Implementation

[0024] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein, and therefore this application is not limited to the specific embodiments disclosed below.

[0026] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0027] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0028] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. In addition, although the terminology used in this application is selected from commonly known and used terms, some terms mentioned in this application's specification may have been chosen by the applicant according to his or her judgment, and their detailed meanings are explained in the relevant sections of this description. Moreover, this application should be understood not only through the actual terms used, but also through the meaning implied by each term.

[0029] Hereinafter, embodiments of this application will be described based on the accompanying drawings. However, the embodiments shown below are examples of gas recovery devices for flow batteries used to embody the technical concept of this application, and the gas recovery device for flow batteries in this application is not specifically defined as follows. Furthermore, in order to facilitate understanding of the scope of the claims, the components corresponding to the components shown in the embodiments are assigned numbers to the components shown in the "Claims" and "Utility Model Content" columns. However, the components shown in the claims are not intended to be specific to the components of the embodiments. In particular, the dimensions, materials, shapes, and relative arrangements of the constituent components described in the embodiments are not intended to limit the scope of this application unless specifically stated otherwise, but are merely illustrative examples.

[0030] However, the dimensions or positional relationships of the components shown in the accompanying drawings are sometimes exaggerated for clarity. Therefore, in the following description, detailed descriptions of the same names and symbols representing the same or homogeneous components are appropriately omitted. Furthermore, the elements constituting this application may be multiple elements composed of the same components, thus allowing one component to function as multiple elements; conversely, multiple components may share the function of one component. Additionally, the content described in some embodiments and implementations can be applied to other embodiments and implementations. Furthermore, in this specification, "upper" is not limited to the case of being formed in contact with an upper surface, but also includes the case of being formed separately on top, and also includes the meaning of an intermediate layer between layers.

[0031] like Figure 1As shown, this application provides a gas recovery device for a flow battery, including: a positive electrode line 110 and a negative electrode line 120, a reaction chamber 130, and an absorption chamber 140. The first port 111 of the positive electrode line 110 is connected to the positive electrode tank (not shown) of the flow battery, and the first port 121 of the negative electrode line 120 is connected to the negative electrode tank (not shown) of the flow battery. The reaction chamber 130 includes a light source generator 131 and a reaction chamber outlet 132. The positive electrode line 110 is connected to the reaction chamber 130 to transfer a first gas generated in the positive electrode tank to the interior of the reaction chamber 130. The negative electrode line 120 is connected to the reaction chamber 130 to transfer a second gas generated in the negative electrode tank to the interior of the reaction chamber 130. The light source generator 131 generates a light source, which promotes the reaction between the first and second gases. An electrolyte inlet 141 is provided at the top of the absorption chamber 140, and an electrolyte outlet 142 is provided at the bottom of the absorption chamber 140. An absorption chamber air inlet 143 and an absorption chamber air outlet 143 are provided on the side wall of the absorption chamber 140. The absorption chamber air inlet 143 is connected to the reaction chamber air outlet 132. The electrolyte inlet 141 and the absorption chamber air outlet 143 are respectively connected to the positive electrode storage tank of the flow battery.

[0032] In this application, the positive and negative electrode storage tanks are devices for storing the electrolyte of a flow battery. This application does not limit the shape or specific structure of the positive and negative electrode storage tanks. It is understood that the gas recovery device can be adjusted according to different positive and negative electrode storage tanks, such as adjusting the dimensions of the positive and negative electrode pipelines. In some embodiments, the electrolyte stored in the positive and negative electrode storage tanks is an acidic electrolyte, such as an electrolyte containing chloric acid (hydrochloric acid and hypochlorous acid, etc.) and mixed acids (containing sulfuric acid and hydrochloric acid). When the electrolyte contains chloride ions, a chlorine evolution side reaction occurs at the positive electrode during the charging process of the flow battery, generating chlorine gas (Cl2), and a hydrogen evolution side reaction occurs at the negative electrode, generating hydrogen gas (H2). In this embodiment, the first gas is chlorine gas, and the second gas is hydrogen gas. The gas obtained from the side reaction needs to be replaced with a displacement gas to carry the chlorine and hydrogen gas into the positive and negative electrode pipelines for subsequent replacement and recovery processing. The displacement gas is a gas that will not react with the first and second gases. In some embodiments, the displacement gas can be any of nitrogen, argon, and carbon dioxide. Therefore, in these embodiments, the positive electrode tank contains a first gas produced by the side reaction, namely chlorine; the negative electrode tank contains a second gas produced by the side reaction, namely hydrogen. When the displacement gas is introduced, the gas flowing through the positive electrode pipeline is the first gas and the displacement gas, and the gas flowing through the negative electrode pipeline is the second gas and the displacement gas. Flow batteries using acid-based electrolytes include vanadium redox flow batteries, zinc-iron flow batteries, and iron-chromium flow batteries.

[0033] Reaction chamber 130 is the site where the first gas and the second gas react. Positive electrode line 110 is connected to reaction chamber 130, transferring the first gas generated in the positive electrode tank to the interior of reaction chamber 130. Negative electrode line 120 is also connected to reaction chamber 130, transferring the first gas generated in the negative electrode tank to the interior of reaction chamber 130. Light source generator 131 generates a light source to promote the reaction between the first gas and the second gas, namely the combination reaction of chlorine and hydrogen, to obtain hydrogen chloride (HCl) gas.

[0034] In some embodiments of this application, such as Figure 1 As shown, the reaction chamber 130 has a reaction chamber inlet 133. The positive electrode line and the negative electrode line are merged and connected to the reaction chamber inlet 133. In these embodiments, the first gas and the second gas are mixed first and then introduced into the reaction chamber for reaction.

[0035] In some embodiments of this application, the reaction chamber 130 may have multiple air inlets, such as two air inlets. A positive electrode line is connected to one air inlet, and a negative electrode line is connected to the other air inlet. In these embodiments, the first gas and the second gas are simultaneously introduced into the reaction chamber and then mixed and reacted.

[0036] In some embodiments of this application, the wavelength of the light source emitted by the light source generator 131 does not exceed 400 nanometers.

[0037] The absorption chamber 140 is a chamber for the positive electrode electrolyte to absorb hydrogen chloride gas. Preferably, the absorption chamber 140 is configured as an absorption tower. An electrolyte inlet 141 is provided at the top of the absorption chamber 140, and the electrolyte inlet 141 is connected to the positive electrode storage tank. The electrolyte is sprayed into the absorption chamber 140 through the electrolyte inlet 141. When the electrolyte is sprayed into the absorption chamber 140, a large number of mist-like liquid particles are formed in the absorption chamber 140. The large number of mist-like liquid particles greatly increases the contact area with the hydrogen chloride gas. An electrolyte outlet 142 is provided at the bottom of the absorption chamber 140 for discharging the electrolyte after absorbing hydrogen chloride gas. An absorption chamber inlet 143 and an absorption chamber outlet 144 are provided on the side wall of the absorption chamber 140. The absorption chamber inlet 143 is connected to the reaction chamber outlet 132, and the absorption chamber outlet 144 is connected to the positive electrode storage tank. In the embodiments of this application, the purpose of connecting the absorption chamber outlet 144 to the positive electrode storage tank is to introduce the remaining first gas into the positive electrode storage tank if the hydrogen of the second gas and the chlorine of the first gas have fully reacted.

[0038] The first and second gases generated by the side reaction react in the reaction chamber, and the reaction products are absorbed in the absorption chamber. The positive electrode electrolyte after absorption flows back to the positive electrode storage tank, which slows down the loss rate of chloride ions in the flow battery and reduces the precipitation of metal salts in the electrode liquid, maintaining a high energy density and energy conversion efficiency. It avoids the problem of adding a large amount of chloric acid solution to replenish chloride ions in practical applications, and reduces the maintenance cost of the flow battery.

[0039] like Figure 2 As shown, in one embodiment of this application, the gas recovery device further includes a mixing chamber 150. The positive electrode line 110 and the negative electrode line 120 are successively connected to the mixing chamber 150, and then to the reaction chamber 130, so that the first gas and the second gas are mixed in the mixing chamber 150 before entering the reaction chamber 130. In some embodiments, the first gas has a higher density than the second gas. Therefore, if the second gas is directly introduced into the reaction chamber 130, the first gas tends to deposit at the bottom of the reaction chamber 130, while the second gas tends to accumulate at the top, making the reaction difficult to complete. The mixing chamber 150 allows for thorough mixing of the first and second gases beforehand, and the mixture, when introduced into the reaction chamber 130, better promotes the chemical reaction between the first and second gases.

[0040] like Figure 2 As shown, in one embodiment of this application, the inner wall of the mixing chamber 150 has two opposing sidewalls 152, and each of the two sidewalls 152 is provided with a plurality of baffles 151, which are staggered to form gas flow channels 153. Figure 2 As shown, both sidewalls 152 extend horizontally. One end of the baffle 151 can be fixedly mounted on the sidewall 152, and the other end extends vertically but does not contact the opposite sidewall 152. That is, there is a gap between the baffle 151 and the opposite sidewall 152 to allow airflow to pass through. Figure 2 The illustration is merely an example. In other embodiments, the two sidewalls 152 may be sidewalls extending in a vertical direction, while the baffle extends in a horizontal direction.

[0041] By setting baffle 151, a longer gas flow channel 153 can be formed. When the first gas and the second gas enter the mixing chamber, they can be fully mixed through the gas flow channel 153 formed by baffle 151.

[0042] like Figure 2As shown, in one embodiment of this application, the gas recovery device further includes a gas flow meter 113. The gas flow meter 113 is respectively disposed in the positive electrode line 110 and the negative electrode line 120, and is used to control the flow rate of the first gas in the positive electrode line 110 to be greater than the flow rate of the second gas in the negative electrode line 120. The ratio of the first gas flow rate to the second gas flow rate is controlled within the range of 1:1 to 10:1. In some embodiments, the hydrogen gas in the second gas is a highly flammable gas that can form an explosive mixture when mixed with air in a certain proportion. Therefore, the safety of the gas recovery device must be ensured during the chemical reaction between the first and second gases. By reducing the flow rate of the second gas and increasing the flow rate of the first gas, the volume of the second gas can be made smaller than the volume of the first gas, allowing the second gas to react completely.

[0043] like Figure 2 As shown, in one embodiment of this application, the gas recovery device further includes a second gas detector 170, which is connected to the absorption chamber outlet 144 and is used to detect whether there is unreacted second gas in the gas discharged from the absorption chamber 140. The gas recovery device also includes a first return pipe 180 and a second return pipe 190, and the mixing chamber 150 further includes a return hole 154. The first return pipe 180 connects the positive electrode tank and the absorption chamber outlet 144, and the second return pipe 190 connects the absorption chamber outlet 144 and the return hole 154. The first return pipe 180 is configured to guide the gas discharged from the absorption chamber outlet 144 to the positive electrode tank when the second gas detector 170 does not detect the second gas; the second return pipe 190 is configured to guide the gas discharged from the absorption chamber outlet 144 to the mixing chamber 150 when the second gas detector 170 detects the second gas.

[0044] The gas recovery device in this embodiment determines the subsequent gas emission path by detecting the presence of a second gas, in some embodiments hydrogen, in the gas discharged from the absorption chamber outlet 144. When the second gas detector 170 does not detect hydrogen, it indicates that the hydrogen has completely reacted. However, the gas discharged from the absorption chamber outlet 144 may still contain excess chlorine. Therefore, the discharged gas is directed to the positive electrode storage tank to absorb the excess chlorine. When the second gas detector 170 detects hydrogen, there is still excess hydrogen that has not participated in the reaction. If this is introduced into the positive electrode storage tank, it could easily cause an explosion. Therefore, the gas discharged from the absorption chamber outlet 144 is reintroduced into the mixing chamber 150 through the return port 154 to continue reacting with chlorine, thus improving the safety of the flow battery operation.

[0045] One way to selectively open the first reflux line 180 or the second reflux line 190 based on the presence of hydrogen in the exhaust gas from the absorption chamber outlet 144 is as follows: A three-way valve is installed between the second gas detector 170, the first reflux line 180, and the second reflux line 190. Both the second gas detector 170 and the three-way valve are connected to a microcontroller. The microcontroller controls the flow path of the three-way valve based on the result from the second gas detector 170, thereby selectively opening either the first reflux line 180 or the second reflux line 190. The second gas detector is a hydrogen detector.

[0046] like Figure 2 As shown in one embodiment of this application, the absorption chamber 140 is provided with a material area, an air inlet area, and an air outlet area. The material area is filled with material, the air inlet 143 is located in the air inlet area, and the air outlet 144 is located in the air outlet area. The material area is filled with material, which includes a large amount of loose particles. The material includes any one or more of graphite balls, graphite rings, and PP plastic balls. The electrolyte sprayed from the electrolyte inlet 141 of the absorption chamber 140 flows between the loose particles, increasing the contact area between hydrogen chloride gas and electrolyte, enabling the electrolyte to fully absorb hydrogen chloride gas. The material also has a certain retention effect on the electrolyte, preventing the electrolyte from falling directly to the bottom of the absorption chamber 140, increasing the contact time between the electrolyte and hydrogen chloride gas, and also enabling the electrolyte to fully absorb hydrogen chloride gas. The air inlet 143 of the absorption chamber is located in the air inlet area, and the air outlet 144 of the absorption chamber is located in the air outlet area to prevent the material from clogging the air inlet 143 and the air outlet 144 of the absorption chamber under certain circumstances, thereby affecting the flow of gas.

[0047] This application does not limit the shape or specific structure of the material area. Figure 2 The material area shown is merely an illustrative example. It is understood that the gas recovery device can design the material area according to different application scenarios. For example, the material area can be set as a cylinder, cuboid, or polyhedron, etc.

[0048] like Figure 2 As shown, in one embodiment of this application, the height of the absorption chamber inlet 143 is lower than the height of the absorption chamber outlet 144. By setting the height, hydrogen chloride gas flowing in from the absorption chamber inlet 143 can fill the absorption chamber 140, allowing the electrolyte to better absorb the hydrogen chloride gas.

[0049] like Figure 2As shown, in one embodiment of this application, the gas recovery device includes a pump device 160, which is disposed on the positive electrode line 110, the negative electrode line 120, the electrolyte inlet 141, and the electrolyte outlet 142. The positive electrode line 110 and the negative electrode line 120 are gas lines, and the pump device 160 is a gas pump that provides power to the gas in the positive electrode line 110 and the negative electrode line 120. The electrolyte inlet 141 and the electrolyte outlet 142 are liquid inlets and outlets, and the pump device 160 is a magnetic pump that provides power to the flow of the electrolyte. A pump device 160 may also be disposed on the second return line 190, which is also a gas pump that provides power to the gas discharged from the gas outlet 144 of the absorption chamber.

[0050] The following describes the operation of the gas recovery device using a specific example. The flow battery used is a vanadium redox flow battery, the electrolyte is a vanadium chloride electrolyte, the absorption chamber 140 is an absorption tower, and the replacement gas introduced into the positive electrode line 110 and the negative electrode line 120 is nitrogen. After the vanadium chloride electrolyte flow battery system has been running for a period of time, due to the occurrence of side reactions at the positive and negative electrodes, chlorine will accumulate in the positive electrode tank, and hydrogen will accumulate in the negative electrode tank. At this time, nitrogen is introduced into the positive and negative electrode tanks respectively, so that chlorine and hydrogen flow into the positive electrode line 110 and the negative electrode line 120 of the gas recovery device, respectively. The chlorine and nitrogen in the positive electrode line 110, and the hydrogen and nitrogen in the negative electrode line 120, are simultaneously introduced into the mixing chamber 150. The gas flow rate in the positive electrode line 110 is 5 L / min, and the gas flow rate in the negative electrode line 120 is 1 L / min. Chlorine and nitrogen from the positive electrode line 110, and hydrogen and nitrogen from the negative electrode line 120, enter the mixing chamber 150 and are mixed by several baffles 151. After being uniformly mixed, the mixture is introduced into the reaction chamber 130. The light source generator 131 in the reaction chamber 130 emits strong ultraviolet light, causing chlorine and hydrogen to react chemically to generate gaseous hydrogen chloride. The hydrogen chloride gas, along with nitrogen, enters the absorption chamber 140 through the absorption chamber inlet 143. Simultaneously, the electrolyte from the positive electrode storage tank is sprayed into the absorption chamber from the electrolyte inlet 141 at a flow rate of 10 L / min, and comes into full contact with the hydrogen chloride and nitrogen gas in the material area, where the hydrogen chloride gas is absorbed by the electrolyte. The electrolyte, after absorbing hydrogen chloride, returns to the positive electrode storage tank through the electrolyte outlet 142. The remaining gas after the absorption of hydrogen chloride passes through the second gas detector 170. If no hydrogen is detected, it returns to the positive electrode storage tank through the first return line 180 to continue replacing the chlorine in the positive electrode storage tank. If the presence of hydrogen is detected, it returns to the mixing chamber 150 through the second return line 190, continues to mix with chlorine, and then flows to the reaction chamber 130 for reaction.

[0051] This application proposes a gas recovery device for a flow battery, in which the first and second gases generated by the side reaction react in the reaction chamber, are absorbed in the absorption chamber, and flow back to the positive electrode tank. This slows down the loss rate of chloride ions in the flow battery and reduces the precipitation of electrolyte metal salts; maintains high energy density and energy conversion efficiency; avoids the problem of adding large amounts of chloric acid solution to replenish chloride ions in practical applications, and reduces the maintenance cost of the flow battery.

[0052] While the foregoing disclosure has discussed various examples of embodiments of the present application that are currently considered useful, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments. Rather, the claims are intended to cover all modifications and equivalent combinations that conform to the spirit and scope of the embodiments of the present application. For example, although the system components described above can be implemented by hardware devices, they can also be implemented solely by software solutions, such as installing the described system on existing servers or mobile devices.

[0053] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the present application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0054] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of scope in some embodiments of this application are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

Claims

1. A gas recovery device for a flow battery, characterized in that, include: A positive electrode line and a negative electrode line, wherein the first port of the positive electrode line is connected to the positive electrode tank of the flow battery, and the first port of the negative electrode line is connected to the negative electrode tank of the flow battery; The reaction chamber includes a light source generator and a gas outlet. The positive electrode pipeline is connected to the reaction chamber and is used to transfer a first gas generated in the positive electrode tank to the interior of the reaction chamber. The negative electrode pipeline is connected to the reaction chamber and is used to transfer a second gas generated in the negative electrode tank to the interior of the reaction chamber. The light source generator is used to generate a light source and the light source is used to promote the reaction between the first gas and the second gas. The absorption chamber has an electrolyte inlet at its top and an electrolyte outlet at its bottom. The side wall of the absorption chamber has an absorption chamber air inlet and an absorption chamber air outlet. The absorption chamber air inlet is connected to the reaction chamber air outlet. The electrolyte inlet and the absorption chamber air outlet are respectively connected to the positive electrode storage tank of the flow battery.

2. The gas recovery device as described in claim 1, characterized in that, It also includes a mixing chamber, and the positive electrode line and the negative electrode line are first connected to the mixing chamber and then connected to the reaction chamber, so that the first gas and the second gas are mixed in the mixing chamber before entering the reaction chamber.

3. The gas recovery device as described in claim 2, characterized in that, It also includes a gas flow meter, which is disposed in the positive electrode pipeline and the negative electrode pipeline; The gas flow meter is used to control the first gas flow rate in the positive electrode pipeline to be greater than the second gas flow rate in the negative electrode pipeline.

4. The gas recovery device as described in claim 3, characterized in that, The ratio of the first gas flow rate to the second gas flow rate is controlled to be 1:1-10:

1.

5. The gas recovery device according to any one of claims 2-4, characterized in that, It also includes a second gas detector, a first reflux line and a second reflux line. The mixing chamber includes a reflux hole. The second gas detector is connected to the gas outlet of the absorption chamber. The first reflux line is connected to the positive electrode storage tank and the gas outlet of the absorption chamber. The second reflux line is connected to the gas outlet of the absorption chamber and the reflux hole. The first return pipeline is configured to divert the gas discharged from the gas outlet of the absorption chamber to the positive electrode storage tank when the second gas detector does not detect the second gas. The second return line is configured to guide the gas discharged from the outlet of the absorption chamber to the mixing chamber when the second gas detector detects the second gas.

6. The gas recovery device according to any one of claims 1-4, characterized in that, The absorption chamber is provided with a material area, an air inlet area, and an air outlet area. The material area is filled with material. The air inlet of the absorption chamber is located in the air inlet area, and the air outlet of the absorption chamber is located in the air outlet area.

7. The gas recovery device according to any one of claims 1-4, characterized in that, The height of the air inlet of the absorption chamber is lower than the height of the air outlet of the absorption chamber.

8. The gas recovery device according to any one of claims 1-4, characterized in that, It also includes a pump device, which is disposed in the positive electrode line, the negative electrode line, the electrolyte inlet and the electrolyte outlet.

9. The gas recovery device as described in claim 2, characterized in that, The inner wall of the gas mixing chamber has two oppositely arranged side walls, and each of the two side walls is provided with a number of baffles. The number of baffles are staggered to form a gas flow channel.

10. The gas recovery device as described in claim 6, characterized in that, The material includes any one or more of graphite spheres, graphite rings, and PP plastic spheres.

11. The gas recovery device as described in claim 1, characterized in that, The wavelength of the light source does not exceed 400 nanometers.

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