An electrochemical cell stack

Abstract

The application relates to the technical field of energy, and provides a stack of a liquid flow battery, which comprises at least one liquid flow battery unit; the liquid flow battery unit at least comprises a first integrated plate, a second integrated plate and a barrier located between the first integrated plate and the second integrated plate; the first integrated plate comprises a first body part and a first electrode, a first flow channel part is formed on one side of the first body part close to the second integrated plate, and the first electrode covers at least part of the surface of the first flow channel part; the stack of the liquid flow battery further comprises a first current collecting plate in conduction with the first electrode; the first current collecting plate comprises a first current collecting part and a first protruding part, the first current collecting part is used for collecting a first current generated by the first electrode, the first protruding part is connected with the first current collecting part and is used for connecting a target component and transmitting the first current to the target component; and the target component comprises a load or an external circuit.

Description

Technical Field

[0001] This application relates to the field of energy technology, and in particular to a flow battery stack. Background Technology

[0002] Vanadium redox flow batteries (VRFBs) utilize vanadium ions in different oxidation states as charge carriers in a sulfuric acid aqueous solution to achieve the interconversion of electrical and chemical energy, making them a key technology for grid-scale energy storage applications. VRFB stacks consist of multiple independent components, requiring complex assembly procedures and specialized tools for maintenance. Furthermore, sealing failures are prone to occur at component connections. Therefore, optimizing the flow battery structure, reducing assembly complexity, and minimizing potential failure modes have become urgent problems to be solved. Summary of the Invention

[0003] The main objective of this application is to provide a flow battery stack that aims to reduce the assembly complexity of flow batteries and reduce potential failure modes of flow batteries.

[0004] In a first aspect, this application provides a flow battery stack, the flow battery stack including at least one flow battery unit; the flow battery unit includes at least a first integrated plate, a second integrated plate, and a barrier member located between the first integrated plate and the second integrated plate; The first integrated board includes a first body portion and a first electrode. A first flow channel portion is formed on the side of the first body portion near the second integrated board, and the first electrode covers at least a portion of the surface of the first flow channel portion. The second integrated board includes a second body portion and a second electrode. A second flow channel portion is formed on the side of the second body portion near the first integrated board, and the second electrode covers at least a portion of the surface of the second flow channel portion. The flow battery stack also includes a first current collector connected to the first electrode and a second current collector connected to the second electrode; The first current collector includes a first current collector and a first protrusion. The first current collector is used to collect the first current generated by the first electrode. The first protrusion is connected to the first current collector and is used to connect to the target component and transmit the first current to the target component. The second current collector includes a second current collector and a second protrusion. The second current collector is used to collect the second current generated by the second electrode. The second protrusion is connected to the second current collector and is used to connect to the target component and transmit the second current to the target component. The target component includes a load or an external circuit.

[0005] In some embodiments, the first integrated board is further provided with a first manifold interface, and the second integrated board is further provided with a second manifold interface. The first manifold interface and the second manifold interface are used to connect to an external manifold, which is used to provide electrolyte to the first flow channel portion of the first integrated board and the second flow channel portion of the second integrated board.

[0006] In some embodiments, the first integrated board is provided with a first electrolyte inlet and a first electrolyte outlet; the first electrolyte inlet is connected to a first electrolyte inlet manifold and is used to provide the first electrolyte required for the electrochemical reaction to the first flow channel; the first electrolyte outlet is connected to a first electrolyte outlet manifold and is used to receive the first electrolyte that has undergone the electrochemical reaction in the first flow channel. The second integrated board is provided with a second electrolyte inlet and a second electrolyte outlet; the second electrolyte inlet is connected to a second electrolyte inlet manifold and is used to provide the second electrolyte required for the electrochemical reaction to the second flow channel; the second electrolyte outlet is connected to a second electrolyte outlet manifold and is used to receive the second electrolyte that has undergone the electrochemical reaction in the second flow channel.

[0007] In some embodiments, the first electrode is fixedly disposed on at least a portion of the surface of the first flow channel portion by conductive adhesive, and the first electrode covers the position corresponding to the first flow channel portion; The second electrode is fixedly disposed on at least a portion of the surface of the second flow channel portion by conductive adhesive, and the second electrode covers the position corresponding to the second flow channel portion.

[0008] In some embodiments, the area of ​​the first flow channel portion is 50%-75% of the area of ​​the first body portion, and the area of ​​the first electrode is greater than or equal to the area of ​​the first flow channel portion. And / or, the area of ​​the second flow channel is 50%-75% of the area of ​​the second body portion, and the area of ​​the second electrode is greater than or equal to the area of ​​the second flow channel.

[0009] In some embodiments, the first flow channel includes a plurality of straight flow channels and a plurality of connecting flow channels. The plurality of straight flow channels are arranged parallel and spaced apart in a first direction, and the connecting flow channels are arranged spaced apart in a second direction. Adjacent straight flow channels are connected through the connecting flow channels. And / or, the second flow channel includes a plurality of straight flow channels and a plurality of connecting flow channels, wherein the plurality of straight flow channels are arranged parallel and spaced apart in a first direction, the connecting flow channels are arranged spaced apart in a second direction, and adjacent two straight flow channels are connected through the connecting flow channels; Wherein, the first direction and the second direction are perpendicular to each other.

[0010] In some embodiments, the first flow channel includes a plurality of finger-shaped flow channels that are parallel to each other and spaced apart in a third direction. The first finger-shaped flow channels in the finger-shaped flow channels are interconnected by a first through-flow channel in a second direction to form a first interdigitated flow channel. The second finger-shaped flow channels in the finger-shaped flow channels are interconnected by a second through-channel in a second direction to form a second interdigitated flow channel. The first finger-shaped flow channels and the second finger-shaped flow channels are alternately arranged to form an interdigitated flow channel. And / or, the second flow channel includes a plurality of finger strip flow channels that are parallel to each other and spaced apart in a third direction. The first finger strip flow channels in the finger strip flow channels are interconnected by a first through flow channel in a second direction to form a first interdigitated flow channel. The second finger strip flow channels in the finger strip flow channels are interconnected by a second through channel in a second direction to form a second interdigitated flow channel. The first finger strip flow channels and the second finger strip flow channels are staggered to form an interdigitated flow channel.

[0011] In some embodiments, the flow battery stack further includes a first end plate, a second end plate, and a fixing member, the fixing member extending along the thickness direction of the stack for fixing at least one flow battery unit in the stack, the first end plate and the second end plate being respectively mounted on opposite sides of the stack.

[0012] In some embodiments, both the first body portion and the second body portion are graphite body portions, and both the first electrode and the second electrode are carbon felt electrodes or carbon paper electrodes.

[0013] In some embodiments, the first integrated board includes a first body portion and a first electrode, the first body portion having first flow channel portions formed on both sides, and the first electrode covering at least a portion of the surface of the first flow channel portion; The second integrated board includes a second body portion and a second electrode. Second flow channels are formed on both sides of the second body portion, and the second electrode covers at least a portion of the surface of the second flow channels.

[0014] This application provides a flow battery stack. The stack integrates a first electrode and a first flow channel portion into a first integrated plate in a first body portion, and integrates a second electrode and a second flow channel portion into a second integrated plate in a second body portion. This eliminates the need for assembling bipolar plates, flow channel plates, and electrodes during flow battery installation, reduces the assembly complexity of the flow battery, decreases potential failure modes, and optimizes the flow battery structure. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 An exploded view of the structure of a flow battery stack provided in one embodiment of this application; Figure 2 A physical diagram of a first integrated board provided in an embodiment of this application; Figure 3 A cross-sectional view of a first integrated board provided in an embodiment of this application; Figure 4 An exploded view of the structure of a flow battery stack provided in another embodiment of this application; Figure 5 A schematic diagram of the structure of a first flow channel and a second flow channel provided in an embodiment of this application; Figure 6 This is a schematic diagram of another first flow channel and a second flow channel provided in an embodiment of this application.

[0017] Explanation of reference numerals in the attached drawings: 10, Flow battery unit; 11, First integrated plate; 12, Second integrated plate; 13, Barrier component; 111, First body part; 112, First electrode; 113, First flow channel part; 121, Second body part; 122, Second electrode; 123, Second flow channel part; 14, First collector plate; 15, Second collector plate; 16, First end plate; 17, Second end plate; 18, Fixing component; 100, Straight flow channel; 101, Continuous flow channel; 1101, First electrolyte inlet; 1102, First electrolyte outlet; 1201, Second electrolyte inlet; 1202, Second electrolyte outlet; 102, Finger strip flow channel; 1021, First through flow channel; 1022, Second through flow channel. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] In the description of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0020] It is understood that descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0021] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0022] Please refer to Figure 1 , Figure 1 This is an exploded view of the structure of a flow battery stack provided in one embodiment of this application.

[0023] like Figure 1 As shown, one embodiment of this application provides a flow battery stack including at least one flow battery unit 10; the flow battery unit 10 includes at least a first integrated plate 11, a second integrated plate 12, and a barrier member 13 located between the first integrated plate 11 and the second integrated plate 12. The first integrated plate 11 includes a first body portion 111 and a first electrode 112. A first flow channel portion 113 is formed on the side of the first body portion 111 near the second integrated plate 12. Figure 1 (Not shown), the first electrode 112 covers at least a portion of the surface of the first flow channel portion 113; The second integrated plate 12 includes a second body portion 121 and a second electrode 122. A second flow channel portion 123 is formed on the side of the second body portion 121 near the first integrated plate 11, and the second electrode 122 covers at least a portion of the surface of the second flow channel portion 123. The flow battery stack also includes a first current collector 14 connected to the first electrode 112 and a second current collector 15 connected to the second electrode 122; The first current collector 14 includes a first current collector and a first protrusion. The first current collector is used to collect the first current generated by the first electrode 112. The first protrusion is connected to the first current collector and is used to connect to the target component and transmit the first current to the target component. The second current collector 15 includes a second current collector section and a second protrusion section. The second current collector section is used to collect the second current generated by the second electrode 122. The second protrusion section is connected to the second current collector section 123 and is used to connect to the target component and transmit the second current to the target component. The target component includes a load or an external circuit.

[0024] For example, a first flow channel 113 is formed on at least one side of the first body portion 111, and a second flow channel 123 is formed on at least one side of the first body portion 111. When the first flow channel 113 is formed on one side of the first body portion 111, the first body portion 111 serves as a single plate of the flow battery unit 10; when the second flow channel 123 is formed on one side of the first body portion 111, the first body portion 111 serves as a single plate of the flow battery unit 10.

[0025] For example, by integrating the first electrode 112 and the first flow channel portion 113 into the first body portion 111 to form the first integrated plate 11, and integrating the second electrode 122 and the second flow channel portion 123 into the second body portion 121 to form the second integrated plate 12, the assembly requirements of the monopole plate (or bipole plate), flow channel plate and electrode are avoided during the installation of the flow battery, reducing the assembly complexity of the flow battery, reducing the potential failure modes of the flow battery, optimizing the structure of the flow battery, and thus improving the maintainability of the stack.

[0026] For example, the stack of the flow battery can be a vanadium redox flow battery stack.

[0027] The first integrated plate 11 can be a membrane electrode assembly (MEAs) integrating a first body portion 111, a first electrode 112, and a first flow channel portion 113. Alternatively, it can also include an electrode frame in addition to the first body portion 111, the first electrode 112, and the first flow channel portion 113, forming a membrane electrode gasket assembly (MEGAs). Due to the integrated design of the first electrode 112 and the first body portion 111, the electrode frame for fixing the electrode can be omitted. Understandably, the second integrated plate 12 also has a similar configuration, which will not be described in detail here.

[0028] Please refer to Figure 2 , Figure 2 A physical diagram of a first integrated board 11 provided in an embodiment of this application.

[0029] like Figure 2As shown, the working principle of the flow battery is based on the redox reaction of active substances in the electrolyte to realize the mutual conversion of electrical energy and chemical energy. The first electrode 112 is in close contact with the surface of the first flow channel 113, and the second electrode 122 is in close contact with the surface of the second flow channel 123, so that when the electrolyte flows through the flow channel covered by the electrode, the electrode serves as the site of electrochemical reaction, providing a reaction interface for the active substances in the electrolyte.

[0030] For example, the first flow channel portion 113 is integrally formed on the first body portion 111, and the second flow channel portion 123 is integrally formed on the second body portion 121.

[0031] In some embodiments, the first integrated plate 11 includes a first body portion 111 and a first electrode 112. First flow channel portions 113 are formed on both sides of the first body portion 111, and the first electrode 112 covers at least a portion of the surface of the first flow channel portion 113. The second integrated plate 12 includes a second body portion 121 and a second electrode 122. Second flow channel portions 123 are formed on both sides of the second body portion 121, and the second electrode 122 covers at least a portion of the surface of the second flow channel portion 123.

[0032] For example, when the first flow channel portion 113 is formed on both sides of the first body portion 111, the first body portion 111 acts as a bipolar plate of the flow battery unit 10; when the second flow channel portion 123 is formed on both sides of the first body portion 111, the first body portion 111 acts as a bipolar plate of the flow battery unit 10.

[0033] In some embodiments, the first integrated plate 11 is further provided with a first manifold interface, and the second integrated plate 12 is further provided with a second manifold interface. The first manifold interface and the second manifold interface are used to connect with an external manifold, which is used to provide electrolyte to the first flow channel portion 113 of the first integrated plate 11 and the second flow channel portion 123 of the second integrated plate 12.

[0034] For example, an external manifold is connected to an electrolyte storage tank via a liquid pump to provide electrolyte to the first flow channel 113 and the second flow channel 123. Therefore, a manifold interface also needs to be provided on the integrated plate. Specifically, when the first integrated plate 11 and the second integrated plate 12 are unipolar plates, the first integrated plate 11 is also provided with a first manifold interface to provide the first electrolyte to the first flow channel 113 on the first integrated plate 11; the second integrated plate 12 is also provided with a second manifold interface to provide the second electrolyte to the second flow channel 123 on the second integrated plate 12. The types of the first electrolyte and the second electrolyte are not limited here; for example, the first electrolyte can be a positive electrolyte and the second electrolyte can be a negative electrolyte.

[0035] For example, when the first integrated plate 11 and the second integrated plate 12 are bipolar plates, the first integrated plate 11 is provided with a first manifold interface and a second manifold interface, and the second integrated plate 12 is provided with a first manifold interface and a second manifold interface. That is to say, both the first integrated plate 11 and the second integrated plate 12 require positive electrolyte and negative electrolyte.

[0036] Please refer to Figure 4 , Figure 4 An exploded view of the structure of a flow battery stack provided for another embodiment of this application.

[0037] like Figure 4 As shown, the first integrated plate 11 and the second integrated plate 12 have both monopole plates located on both sides of the fuel cell stack and bipole plates located in the middle of the fuel cell stack; specifically, Figure 4 The first integrated plate 11 in the fuel cell stack acts as a monopole plate, and the second integrated plate 12 in the fuel cell stack acts as a bipole plate.

[0038] Understandably, since a single plate only requires one type of electrolyte, when the first integrated plate 11 and / or the second integrated plate 12 acts as a single plate, it is provided with two manifold interfaces for inputting and outputting one of the positive electrolyte and the negative electrolyte; when the first integrated plate 11 and / or the second integrated plate 12 acts as a single plate, it is provided with four manifold interfaces for inputting and outputting the positive electrolyte and the negative electrolyte.

[0039] Please refer to Figure 3 , Figure 3 This is a cross-sectional view of a first integrated board provided in an embodiment of this application.

[0040] like Figure 3 As shown, in some embodiments, the first integrated plate 11 is provided with a first electrolyte inlet 1101 and a first electrolyte outlet 1102; the first electrolyte inlet 1101 is connected to the first electrolyte inlet manifold and is used to provide the first electrolyte required for the electrochemical reaction to the first flow channel 113; the first electrolyte outlet 1102 is connected to the first electrolyte outlet manifold and is used to receive the first electrolyte that has undergone the electrochemical reaction in the first flow channel 113. The second integrated plate 12 is provided with a second electrolyte inlet 1201 and a second electrolyte outlet 1202; the second electrolyte inlet 1201 is connected to the second electrolyte inlet manifold and is used to provide the second electrolyte required for the electrochemical reaction to the second flow channel 123; the second electrolyte outlet 1202 is connected to the second electrolyte outlet manifold and is used to receive the second electrolyte that has undergone the electrochemical reaction in the second flow channel.

[0041] like Figure 3As shown, both the positive and negative electrolytes require manifolds in both input and output directions. For example, the first integrated plate 11 is provided with a first electrolyte inlet 1101 and a first electrolyte outlet 1102. The first electrolyte in the first electrolyte inlet manifold enters the first flow channel 113 through the first electrolyte inlet 1101, undergoes a chemical reaction in the first flow channel 113, and then enters the first electrolyte outlet manifold through the first electrolyte outlet 1102. The structure of the second integrated plate 12 is similar to that of the first integrated plate 11, and will not be described in detail here.

[0042] In some embodiments, the first electrode 112 is fixedly disposed on at least a portion of the surface of the first flow channel portion 113 by conductive adhesive, and the first electrode 112 covers the position corresponding to the first flow channel portion 113. The second electrode 122 is fixedly disposed on at least a portion of the surface of the second flow channel portion 123 by conductive adhesive, and the second electrode 122 covers the position corresponding to the second flow channel portion 123.

[0043] For example, in order to fix the first electrode 112 to the surface of the first flow channel portion 113 so that the operator does not need to fix the first electrode 112 with the electrode frame when installing the flow battery, the first electrode 112 in this embodiment is attached to at least a portion of the surface of the first flow channel portion 113 with conductive adhesive at the position corresponding to the first flow channel portion 113. A direct conductive connection is provided between the first electrode 112 and the first body portion 111, reducing the contact resistance between the first electrode 112 and the first body portion 111. The structure of the second electrode 122 is similar to that of the first electrode 112, and will not be described in detail here.

[0044] In some embodiments, the area of ​​the first flow channel portion 113 is 50%-75% of the area of ​​the first body portion 111, and the area of ​​the first electrode 112 is greater than or equal to the area of ​​the first flow channel portion 113. And / or, the area of ​​the second flow channel 123 is 50%-75% of the area of ​​the second body 121, and the area of ​​the second electrode 122 is greater than or equal to the area of ​​the second flow channel 123.

[0045] For example, in order to improve the area utilization rate of the first body portion 111, the area occupied by the first flow channel portion 113 on the surface of the first body portion 111 needs to be as large as possible; however, in order to prevent mixing and cross-contamination between electrolytes, the area occupied by the first flow channel portion 113 on the surface of the first body portion 111 cannot be too large. In the embodiments of this application, 50%-75% of the surface area of ​​the first body portion 111 is set as the first flow channel portion 113, which improves the area utilization rate while avoiding the mixing of electrolytes.

[0046] For example, in order for the electrolyte flowing through the first flow channel 113 to react sufficiently in the first electrode 112, the area of ​​the first electrode 112 needs to be greater than or equal to the area of ​​the first flow channel 113.

[0047] Understandably, the structure of the second integrated board 12 is similar to that of the first integrated board 11, and will not be described in detail here.

[0048] Please refer to Figure 5 , Figure 5 This is a schematic diagram of the structure of a first flow channel 113 and a second flow channel 123 provided in an embodiment of this application.

[0049] like Figure 5 As shown, in some embodiments, the first flow channel 113 includes a plurality of straight flow channels 100 and a plurality of connecting flow channels 101. The plurality of straight flow channels 100 are arranged parallel and spaced apart in a first direction, and the connecting flow channels 101 are arranged spaced apart in a second direction. Adjacent straight flow channels 100 are connected 101 through the connecting flow channels. And / or, the second flow channel 123 includes a plurality of straight flow channels 100 and a plurality of connecting flow channels 101. The plurality of straight flow channels 100 are arranged parallel and spaced apart in a first direction, and the connecting flow channels 101 are arranged spaced apart in a second direction. Adjacent straight flow channels 100 are connected 101 through connecting flow channels. Wherein, the first direction and the second direction are perpendicular to each other.

[0050] like Figure 5 As shown, multiple parallel and spaced-apart straight flow channels 100 are connected by multiple connecting flow channels 101 to form a serpentine flow channel. The first electrolyte inlet and the first electrolyte outlet are located at the beginning and end points of the serpentine flow channel, respectively. Understandably, the structure of the second integrated plate 12 is similar to that of the first integrated plate 11, and will not be described in detail here.

[0051] Please refer to Figure 6 , Figure 6 This is a schematic diagram of another first flow channel 113 and second flow channel 123 provided in an embodiment of this application.

[0052] like Figure 6 As shown, in some embodiments, the first flow channel 113 includes a plurality of finger flow channels 102 that are parallel to each other and spaced apart in a third direction. The first finger flow channels in the finger flow channels 102 are interconnected by a first through flow channel 1021 in a second direction to form a first interdigitated flow channel. The second finger flow channels in the finger flow channels 102 are interconnected by a second through channel 1022 in a second direction to form a second interdigitated flow channel. The first finger flow channels and the second finger flow channels are alternately arranged to form an interdigitated flow channel. And / or, the second flow channel 123 includes a plurality of finger flow channels 102 arranged parallel to each other and spaced apart in a third direction. The first finger flow channels in the finger flow channels 102 are interconnected by a first through flow channel 1021 in a second direction to form a first interdigitated flow channel. The second finger flow channels in the finger flow channels 102 are interconnected by a second through channel 1022 in a second direction to form a second interdigitated flow channel. The first finger flow channels and the second finger flow channels are arranged alternately to form an interdigitated flow channel.

[0053] like Figure 6 As shown, the first and second interdigitated channels intersect to form an interdigitated channel, wherein the first electrolyte inlet and the first electrolyte outlet are located in the first and second interdigitated channels, respectively. Understandably, the structure of the second integrated plate 12 is similar to that of the first integrated plate 11, and will not be described in detail here.

[0054] For example, the first flow channel 113 and the second flow channel 123 provide a uniform electrolyte distribution on the electrode surfaces through dedicated flow channels parallel to the surfaces of the first electrode 112 and the second electrode 122, conforming to flow structure principles. This approach, in contrast to a flow-through design, can reduce pressure drop while maintaining sufficient mass transfer to the electrode surfaces.

[0055] In some embodiments, the flow battery stack further includes a first end plate 16, a second end plate 17, and a fixing member 18. The fixing member 18 extends along the thickness direction of the stack and is used to fix at least one flow battery unit 10 in the stack. The first end plate 16 and the second end plate 17 are respectively installed on opposite sides of the stack.

[0056] like Figure 1 As shown, a first end plate 16 and a second end plate 17 are mounted on both sides of the flow battery stack, and the first end plate 16 and the second end plate 17 are connected by a fastener 18. Figure 4 As shown, the fastener 18 includes multiple fastening strips for connecting the first end plate 16 and the second end plate 17 and fixing at least one flow battery unit 10 in the stack.

[0057] In some embodiments, the first body portion 111 and the second body portion 121 are both graphite body portions, and the first electrode 112 and the second electrode 122 are both carbon felt electrodes or carbon paper electrodes. For example, graphite has good electrical conductivity, with a conductivity of 40 S / cm to over 114 S / cm, which can reduce the internal resistance of the battery and improve the energy conversion efficiency. It also has excellent chemical and electrochemical stability, maintaining electrochemical stability in an aggressive vanadium-sulfuric acid electrolyte environment. Therefore, graphite is used to fabricate the first body part 111 and the second body part 121.

[0058] For example, carbon felt has a high porosity, resulting in a large surface area that provides a good reaction site for electrochemical reactions, and it is chemically / electrochemically inert, preventing corrosion by the electrolyte. Similarly, carbon paper has high electrochemical performance, a large specific surface area, and provides more active sites, thereby improving the reaction rate and efficiency of the battery; furthermore, the relatively uniform pore structure of carbon paper facilitates electrolyte penetration and diffusion, contributing to improved overall battery performance. Therefore, carbon felt or carbon paper is used to fabricate the first electrode 112 and the second electrode 122.

[0059] Preferably, the first electrode 112 and the second electrode 122 are made of carbon felt.

[0060] For example, when the flow battery stack needs to be disassembled, the first end plate 16, the second end plate 17, and the fixing member 18 can be removed respectively, disassembling the stack into multiple flow battery units 10, and the flow battery unit 10 can be disassembled into a first integrated plate 11, a second integrated plate 12, and a barrier member 13. The first electrode 112 and the second electrode 122 can be removed from the first integrated plate 11 and the second integrated plate 12 using specific chemical reagents, such as chemical solvents capable of dissolving conductive adhesive. This allows for the disassembly and recycling of different components in the stack. For example, the aging degree of the barrier member 13, the first electrode 112, and the second electrode 122 can be judged by visual inspection, and components with a higher degree of aging can be replaced. Since the power subsystem components in existing vanadium redox flow battery designs typically need to be replaced after 10 years of operation, while the design life of the entire system is 20-30 years, the flow battery stack provided in this application embodiment conforms to the principle of circular economy, which is conducive to the recycling and reuse of components or their recyclable applications. Furthermore, it eliminates the need for prefabricated gaskets, manual assembly of threaded rods, and specialized tools for installing flow channel plates and electrode components, reducing the number of sealing interfaces and simplifying fuel cell stack installation and disassembly.

[0061] Specifically, when it is necessary to disassemble the fuel cell stack, the external manifold and power supply line connected to the fuel cell stack can be disconnected first and the end plate removed. Individual components can be reused after a simple water rinsing procedure or a solvent rinsing procedure, or unmixed recycling can be performed if reuse is not feasible, without causing component breakage or damage.

[0062] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0063] It should also be understood that the term "and / or" as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations. It should be noted that, herein, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0064] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. The above descriptions are merely specific implementations of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An electrochemical stack of a flow battery, characterized by The flow battery stack includes at least one flow battery unit; the flow battery unit includes at least a first integrated plate, a second integrated plate, and a barrier located between the first integrated plate and the second integrated plate; The first integrated board includes a first body portion and a first electrode. A first flow channel portion is formed on the side of the first body portion near the second integrated board, and the first electrode covers at least a portion of the surface of the first flow channel portion. The second integrated board includes a second body portion and a second electrode. A second flow channel portion is formed on the side of the second body portion near the first integrated board, and the second electrode covers at least a portion of the surface of the second flow channel portion. The flow battery stack also includes a first current collector connected to the first electrode and a second current collector connected to the second electrode; The first current collector includes a first current collector and a first protrusion. The first current collector is used to collect the first current generated by the first electrode. The first protrusion is connected to the first current collector and is used to connect to the target component and transmit the first current to the target component. The second current collector includes a second current collector and a second protrusion. The second current collector is used to collect the second current generated by the second electrode. The second protrusion is connected to the second current collector and is used to connect to the target component and transmit the second current to the target component. The target component includes a load or an external circuit.

2. The stack of flow batteries of claim 1, wherein, The first integrated board is also provided with a first manifold interface, and the second integrated board is also provided with a second manifold interface. The first manifold interface and the second manifold interface are used to connect with an external manifold, and the external manifold is used to provide electrolyte to the first flow channel of the first integrated board and the second flow channel of the second integrated board.

3. The stack of flow batteries of claim 1, wherein, The first integrated board is provided with a first electrolyte inlet and a first electrolyte outlet; the first electrolyte inlet is connected to a first electrolyte inlet manifold and is used to provide the first electrolyte required for the electrochemical reaction to the first flow channel; the first electrolyte outlet is connected to a first electrolyte outlet manifold and is used to receive the first electrolyte that has undergone the electrochemical reaction in the first flow channel. The second integrated board is provided with a second electrolyte inlet and a second electrolyte outlet; the second electrolyte inlet is connected to a second electrolyte inlet manifold and is used to provide the second electrolyte required for the electrochemical reaction to the second flow channel; the second electrolyte outlet is connected to a second electrolyte outlet manifold and is used to receive the second electrolyte that has undergone the electrochemical reaction in the second flow channel.

4. The stack of flow cells of claim 1, wherein, The first electrode is fixedly disposed on at least a portion of the surface of the first flow channel portion by conductive adhesive, and the first electrode covers the position corresponding to the first flow channel portion; The second electrode is fixedly disposed on at least a portion of the surface of the second flow channel portion by conductive adhesive, and the second electrode covers the position corresponding to the second flow channel portion.

5. The stack of flow cells of claim 4, wherein, The area of ​​the first flow channel is 50%-75% of the area of ​​the first body, and the area of ​​the first electrode is greater than or equal to the area of ​​the first flow channel. And / or, the area of ​​the second flow channel is 50%-75% of the area of ​​the second body portion, and the area of ​​the second electrode is greater than or equal to the area of ​​the second flow channel.

6. The flow cell stack of any one of claims 1-5, wherein, The first flow channel section includes multiple straight flow channels and multiple connecting flow channels. The multiple straight flow channels are parallel and spaced apart in a first direction, and the connecting flow channels are spaced apart in a second direction. Adjacent straight flow channels are connected through the connecting flow channels. And / or, the second flow channel includes a plurality of straight flow channels and a plurality of connecting flow channels, wherein the plurality of straight flow channels are arranged parallel and spaced apart in a first direction, the connecting flow channels are arranged spaced apart in a second direction, and adjacent two straight flow channels are connected through the connecting flow channels; Wherein, the first direction and the second direction are perpendicular to each other.

7. The flow cell stack of any one of claims 1-5, wherein, The first flow channel includes a plurality of finger-shaped flow channels that are parallel to each other and spaced apart in a third direction. The first finger-shaped flow channels in the finger-shaped flow channels are interconnected by a first through-flow channel in a second direction to form a first interdigitated flow channel. The second finger-shaped flow channels in the finger-shaped flow channels are interconnected by a second through-flow channel in a second direction to form a second interdigitated flow channel. The first finger-shaped flow channels and the second finger-shaped flow channels are alternately arranged to form an interdigitated flow channel. And / or, the second flow channel includes a plurality of finger strip flow channels that are parallel to each other and spaced apart in a third direction. The first finger strip flow channels in the finger strip flow channels are interconnected by a first through flow channel in a second direction to form a first interdigitated flow channel. The second finger strip flow channels in the finger strip flow channels are interconnected by a second through channel in a second direction to form a second interdigitated flow channel. The first finger strip flow channels and the second finger strip flow channels are staggered to form an interdigitated flow channel.

8. The stack of flow cells of claim 1, wherein, The flow battery stack also includes a first end plate, a second end plate, and a fixing member. The fixing member extends along the thickness direction of the stack and is used to fix at least one flow battery unit in the stack. The first end plate and the second end plate are respectively installed on opposite sides of the stack.

9. The stack of flow cells of claim 1, wherein, Both the first body portion and the second body portion are graphite body portions, and both the first electrode and the second electrode are carbon felt electrodes or carbon paper electrodes.

10. The flow cell stack of any one of claims 1-5, wherein, The first integrated board includes a first body portion and a first electrode. First flow channels are formed on both sides of the first body portion, and the first electrode covers at least a portion of the surface of the first flow channel portion. The second integrated board includes a second body portion and a second electrode. Second flow channels are formed on both sides of the second body portion, and the second electrode covers at least a portion of the surface of the second flow channels.

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