A flow battery stack and flow frame

Abstract

The application relates to the field of liquid flow batteries, and provides a liquid flow battery stack and a liquid flow frame. The liquid flow battery stack is stacked by a plurality of battery assemblies, and the battery assembly comprises a battery unit and a liquid flow frame. The liquid flow frame comprises a frame body, the frame body is formed with a mounting position for mounting a bipolar plate of the battery unit; a flow guide disc is arranged on the frame body around the mounting position, the flow guide disc is formed with a spiral flow channel, the spiral flow channels are arranged at intervals by liquid flow spacers, and the liquid flow spacers spirally extend between the outer periphery and the inner periphery of the flow guide disc; wherein the outer periphery of the flow guide disc is formed with a liquid flow port in communication with the spiral flow channel, the inner periphery of the flow guide disc is formed with a liquid flow opening in communication with the spiral flow channel, and the liquid flow opening is connected with a manifold. Through the flow guide disc with the spiral flow channel, the flow distance of the electrolyte before entering the bipolar plate is increased, so that the electrolyte resistance is increased, and the parasitic current is reduced.

Description

Technical Field

[0001] This application relates to the field of flow batteries, and more particularly to a flow battery stack and flow frame. Background Technology

[0002] The vanadium redox flow battery is composed of multiple battery cells stacked together. The electrolyte flows between the battery cells. Because the electrolyte is conductive, the electrolytes of different battery cells will form a conductive loop with a potential difference, and the electrolyte will generate parasitic current, which will reduce the coulombic efficiency of the battery system.

[0003] To reduce parasitic current in flow batteries, related technologies require increasing the resistance of the electrolyte. This is typically achieved by reducing the cross-sectional area of ​​the flow channels on the bipolar plates and designing the channels to be more meandering to increase their length. However, excessively long and narrow channels inevitably reduce the electrolyte's circulating pressure and flow rate, leading to a decrease in power density. This limits the application of this structure to low-power-density flow batteries. Therefore, how to reduce parasitic current while maintaining power density has become a pressing problem to be solved. Summary of the Invention

[0004] The main objective of this application is to provide a flow battery stack and a flow battery system that aims to reduce parasitic current while maintaining the power density of the flow battery.

[0005] In a first aspect, this application provides a flow battery stack, which is composed of multiple battery modules stacked together. Each battery module includes a battery cell and a flow frame; the flow frame includes: A frame having mounting positions for mounting the bipolar plates of the battery unit; A flow guide plate is disposed around the mounting position on the frame. The flow guide plate forms a spiral flow channel, which is spaced apart by liquid flow spacers. The liquid flow spacers extend spirally between the outer and inner circumferences of the flow guide plate. The outer periphery of the flow guide plate has a liquid flow port communicating with the spiral flow channel. The liquid flow port is connected to the electrolyte flow channel in the battery cell for electrochemical reactions, so that the electrolyte in the flow guide plate enters the electrolyte flow channel through the liquid flow port, or the electrolyte in the electrolyte flow channel enters the flow guide plate through the liquid flow port. The liquid flow spacer has a liquid flow opening on the inner periphery of the flow guide plate communicating with the spiral flow channel. The liquid flow opening is connected to a manifold, so that the electrolyte in the manifold enters the flow guide plate through the liquid flow opening, or the electrolyte in the flow guide plate enters the manifold through the liquid flow opening. The manifold is connected to the liquid storage tank of the flow battery.

[0006] Secondly, this application provides a fluid flow frame, comprising: A frame having mounting positions for mounting the bipolar plates of the battery unit; A flow guide plate is disposed around the mounting position on the frame. The flow guide plate forms a spiral flow channel, which is spaced apart by liquid flow spacers. The liquid flow spacers extend spirally between the outer and inner circumferences of the flow guide plate. The outer periphery of the flow guide plate has a liquid flow port communicating with the spiral flow channel. The liquid flow port is connected to the electrolyte flow channel in the battery cell for electrochemical reactions, so that the electrolyte in the flow guide plate enters the electrolyte flow channel through the liquid flow port, or the electrolyte in the electrolyte flow channel enters the flow guide plate through the liquid flow port. The liquid flow spacer has a liquid flow opening on the inner periphery of the flow guide plate communicating with the spiral flow channel. The liquid flow opening is connected to a manifold, so that the electrolyte in the manifold enters the flow guide plate through the liquid flow opening, or the electrolyte in the flow guide plate enters the manifold through the liquid flow opening. The manifold is connected to the liquid storage tank of the flow battery.

[0007] The flow battery stack and flow frame provided in this application embodiment, by providing a guide plate with a spiral flow channel on the frame of the flow frame, allows the electrolyte to flow a relatively long distance along the spiral flow channel before entering the bipolar plate of the battery cell, increasing the resistance of the electrolyte and thus reducing the parasitic current between different battery cells; furthermore, the guide plate of each flow frame in the battery stack is directly connected to the manifold, so that the flow rate loss of the electrolyte when entering the electrolyte flow channel of the bipolar plate is within an acceptable range. Attached Figure Description

[0008] 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.

[0009] Figure 1 This is a schematic diagram of the structure of a fluid flow frame provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a battery stack provided in one embodiment of this application; Figure 3 This is a schematic diagram of the structure of a flow guide plate provided in another embodiment of this application; Figure 4 A cross-sectional view of a flow guide plate provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of a flow guide plate provided in one embodiment of this application; Figure 6This is a schematic diagram of the structure of a flow guide plate provided in another embodiment of this application; Figure 7 A schematic diagram showing the connection between the flow guide plate and the bipolar plate according to an embodiment of this application; Figure 8 This is a schematic diagram of the structure of a fluid flow frame provided in an embodiment of this application; Explanation of reference numerals in the attached drawings: 10, frame; 101, mounting position; 20, guide plate; 201, spiral flow channel; 202, liquid flow spacer; 203, liquid flow port; 204, liquid flow opening; 2021, limiting groove; 205, limiting protrusion; 206, docking hole; 2031, first liquid flow port; 2032, second liquid flow port; 207, manifold through hole; 2041, guide component; 30, bipolar plate. Detailed Implementation

[0010] 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.

[0011] It should be understood that the invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, for clarity, the dimensions and relative dimensions of layers and regions may be exaggerated, and the same reference numerals denote the same elements throughout.

[0012] To fully understand this invention, detailed structures and steps will be presented in the following description to illustrate the technical solution proposed by this invention. Preferred embodiments of the invention are described in detail below; however, in addition to these detailed descriptions, the invention may have other embodiments.

[0013] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a fluid flow frame provided in an embodiment of this application.

[0014] like Figure 1 As shown, the fluid flow frame includes: a frame body 10 and a guide plate 20.

[0015] The frame 10 has a mounting position 101 for mounting the bipolar plate of the battery unit. The mounting position 101 may be a hollow mounting position, and the bipolar plate is embedded in the mounting position 101. Electrodes of different polarities and other necessary structures are respectively arranged on both sides of the bipolar plate to form the battery unit.

[0016] The guide plate 20 surrounds the mounting position 101 and is disposed on the frame 10. Specifically, as shown... Figure 1 As shown, four flow guide plates 20 are arranged around the mounting position 101 on the frame 10, respectively for supplying positive electrolyte, returning positive electrolyte, supplying negative electrolyte, and returning negative electrolyte. However, this is not a limitation; the number of flow guide plates 20 on the frame 10 can be fewer or more, and this is not specified here. Integrating multiple flow guide plates 20 onto the frame 10 of the flow frame avoids the system complexity caused by separately setting multiple flow guide plates and reduces the operational complexity during system installation.

[0017] Please refer to Figure 2 , Figure 2 This is a schematic diagram of the structure of a flow guide plate provided in one embodiment of this application. It should be noted that, for clarity of description, the frame 10... Figure 2 And some other figures not shown.

[0018] like Figure 2 As shown, the guide plate 20 has a spiral flow channel 201, which is spaced apart by liquid flow spacers 202, which extend spirally between the outer and inner circumferences of the guide plate 20.

[0019] Understandably, setting the flow channel on the guide plate 20 to a spiral shape increases the flow path length of the electrolyte while reducing the volume of the guide plate, thereby reducing the overall volume of the flow battery unit; furthermore, the spiral flow channel 201 of the guide plate 20 is independent of the bipolar plate and directly connected to the manifold, so that the flow rate loss of the electrolyte is within an acceptable range.

[0020] Specifically, the fluid flow spacer 202 extends spirally within the plane of the guide plate 20. It can be an equidistant spiral extension with a circular inner and outer circumference; or it can extend along a stretching spiral with an elliptical inner and outer circumference. Of course, it is not limited to these. Any structure that can form a spiral flow channel is within the protection scope of this application.

[0021] The guide plate 20 has a liquid flow port 203 on its outer periphery that communicates with the spiral flow channel 201. The liquid flow port 203 is connected to the electrolyte flow channel in the battery cell for electrochemical reaction, so that the electrolyte in the guide plate 20 enters the electrolyte flow channel through the liquid flow port 203, or the electrolyte in the electrolyte flow channel enters the guide plate 20 through the liquid flow port 203. The liquid flow spacer 202 has a liquid flow opening 204 on its inner periphery that communicates with the spiral flow channel 201. The liquid flow opening 204 is connected to the manifold, so that the electrolyte in the manifold enters the guide plate 20 through the liquid flow opening 204, or the electrolyte in the guide plate 20 enters the manifold through the liquid flow opening 204. The manifold is connected to the liquid storage tank of the flow battery.

[0022] Please continue to refer to Figure 2 In some embodiments, a guide member 2041 is formed at the liquid flow opening 204. The extension direction of the guide member 2041 is the same as the flow direction of the electrolyte at the liquid flow opening 204, and the extension length of the guide member 2041 is equal to the thickness of the liquid flow spacer 202. By providing the guide member 2041 at the liquid flow opening 204, the smoothness of the electrolyte entering the liquid flow opening is improved.

[0023] Please refer to Figure 3 , Figure 4 , Figure 3 This is a schematic diagram of the structure of a flow guide plate provided in another embodiment of this application. Figure 4 This is a cross-sectional view of a flow guide plate provided in one embodiment of this application.

[0024] like Figure 3 , Figure 4 As shown, the flow guide plate 20 has a first surface and a second surface that are opposite to and perpendicular to the thickness direction. The liquid flow spacer 202 is disposed on the first surface and forms a limiting groove 2021. The flow guide plate 20 forms a limiting protrusion 205 on the second surface. The limiting protrusion 205 of one of the two adjacent flow guide plates 20 abuts against the limiting groove 2021 of the other flow guide plate.

[0025] Understandable. Figure 2 This is a schematic diagram of the structure of the first surface of the guide plate 20. Figure 3 This is a schematic diagram of the structure of the second surface of the guide plate 20.

[0026] Specifically, multiple battery cells are stacked in a battery stack, and the fluid flow frames of each battery cell are also stacked in the battery stack. In order to improve the stability of the fluid flow frame stack and reduce the complexity of the battery stack, different surfaces of the guide plate 20 are respectively formed with abutting and mating limiting protrusions 205 and limiting grooves 2021. The limiting protrusions 205 and limiting grooves 2021 of two adjacent fluid flow frames in the battery stack abut against each other. This structure facilitates the alignment of the guide plates 20 of multiple fluid flow frames, avoids complex positioning operations, reduces the complexity of battery stack installation, and especially enables the fluid flow frames to be automatically installed under the operation of a robot.

[0027] A connecting component can be provided between the limiting protrusion 205 and the limiting groove 2021. For example, sealant can be filled into the limiting groove 2021 to fix the guide plates 20 on the two adjacent liquid flow frames relatively. Of course, it is not limited to this. The limiting protrusion 205 and the limiting groove 2021 can also be fixed relatively by welding, bonding or form-locking connection. There is no limitation here. Any method of fixing the limiting protrusion 205 and the limiting groove 2021 relatively is within the protection scope of this application.

[0028] Please refer to Figure 5 , Figure 6 , Figure 5 This is a schematic diagram of the structure of a flow guide plate provided in one embodiment of this application; Figure 6 This is a schematic diagram of the structure of a flow guide plate provided in another embodiment of this application.

[0029] like Figure 5 As shown, the fluid port 203 includes a first fluid port 2031 and a second fluid port 2032. The first fluid port 2031 has a mating hole 206, and the wall of the second fluid port 2032 is closed. The first fluid port 2031 and the second fluid port 2032 are connected to form a fluid connector with a mating hole 206.

[0030] Understandably, this application does not limit the position of the mating hole 206. That is to say, the mating hole 206 can also be formed in the second liquid flow port 2032. Correspondingly, the wall of the first liquid flow port 2031 is closed. At this time, the first liquid flow port 2031 and the second liquid flow port 2032 can still be connected to form a liquid flow connector with the mating hole 206, which will not be elaborated here.

[0031] Understandably, the flow connector formed by the docking of the first flow port 2031 and the second flow port 2032 redirects the flow direction of the electrolyte, allowing the electrolyte that originally flowed horizontally in the guide plate 20 to enter the electrolyte channel on the other side of the bipolar plate in a direction perpendicular to the bipolar plate.

[0032] Please refer to Figure 7 , Figure 7 This is a schematic diagram showing the connection between the flow guide plate and the bipolar plate according to an embodiment of this application.

[0033] like Figure 7 As shown, multiple guide plates 20 are connected to bipolar plates 30 respectively. The docking hole 206 is docked with the flow channel opening of the electrolyte flow channel of the battery cell, so that the electrolyte in the guide plate 20 enters the electrolyte flow channel from the docking hole 206 through the flow channel opening, or the electrolyte in the electrolyte flow channel enters the guide plate 20 from the flow channel opening through the docking hole 206.

[0034] In some embodiments, a hollow manifold through-hole 207 is formed on the inner periphery of the flow guide plate 20, and the manifold through-holes 207 of the plurality of flow guide plates 20 constitute a manifold channel for accommodating the manifold, and the manifold passes through the flow guide plates 20 of the plurality of flow frames via the manifold channel.

[0035] Please continue to refer to Figures 5-7 The manifold through holes 207 of multiple guide plates 20 are aligned to form a manifold channel. The manifold connected to the electrolyte storage tank passes through the multiple guide plates 20 via the manifold channel to provide electrolyte to the multiple guide plates 20 or to receive electrolyte from the multiple guide plates 20.

[0036] Specifically, the electrolyte enters and exits the manifold through the liquid flow opening 204 on the guide plate 20, allowing the manifold to be set independently of the bipolar plates of the battery cell. The shape of the manifold through hole 207 can be circular, elliptical, or other shapes, and is not limited here.

[0037] To avoid increasing the height of the battery stack, in some embodiments, the first length of the fluid flow frame in the stacking direction is less than or equal to the second length of the battery cell in the stacking direction. That is, the thickness of the fluid flow frame is less than the thickness of the battery cell, and the overall height of the battery stack depends only on the thickness and number of the battery cells themselves, and is independent of the thickness of the fluid flow frame.

[0038] In some embodiments, the flow frame is made of plastic raw material by injection molding, the plastic raw material including at least one of the following: polyethylene and polypropylene.

[0039] Specifically, the fluid flow frame can be integrally injection molded, or it can be divided into multiple parts, which are injection molded separately and then assembled to form the overall fluid flow frame. The plastic raw materials used for injection molding include, but are not limited to, polyethylene and polypropylene.

[0040] Understandably, manufacturing the fluid flow frame using a mature injection molding process reduces the production cost and difficulty of the fluid flow frame, which is beneficial for its large-scale production and application.

[0041] In some embodiments, the flow guide plate 20 is disposed between the first vertex of the frame 10 and the second vertex of the mounting position 101.

[0042] Please continue to refer to Figure 1 The guide plate 20 is positioned on the frame 10 near the vertex of the mounting position 101 so that the electrolyte can enter and exit the bipolar plate from the position near the vertex of the mounting position 101, thereby improving the rationality of the electrolyte flow channel layout on the bipolar plate.

[0043] like Figure 1As shown, with four guide plates 20 on the frame 10, the four guide plates 20 are respectively positioned close to the four vertices of the mounting position 101.

[0044] Understandably, the number of guide plates 20 on the frame 10 is not limited. Figure 1 The four shown can be more or fewer, and no limit is set here.

[0045] Please see Figure 8 , Figure 8 This is a schematic diagram of the structure of a fluid flow frame provided in an embodiment of this application.

[0046] In some embodiments, the fluid flow port 203 of the fluid flow frame is exposed at the mounting position 101. This allows the electrolyte flow channel on the bipolar plate 30 to mate with the fluid flow port 203 exposed at the mounting position 101 when the bipolar plate 30 is mounted at the mounting position 101. Specifically, the flow channel opening of the electrolyte flow channel on the bipolar plate 30 can mate with the mating hole of the fluid flow port 203.

[0047] Figure 8 This is a schematic diagram showing the bipolar plate installed at mounting position 101. Figure 1 Compared to the schematic diagram without bipolar plates installed, Figure 1 The portion of the fluid flow port 203 exposed at the installation position is blocked by the bipolar plate 30. This is understandable; if... Figure 8 Bipolar plates 30 are further stacked on the electrode frame shown. Figure 8 The liquid flow port 203 exposed at the mounting position will also be blocked by the stacked bipolar plate, thereby connecting the electrolyte flow channel on the bipolar plate 30 with the liquid flow port 203 exposed at the mounting position 101.

[0048] In some embodiments, the frame 10 is used to fix the battery cell in a plane perpendicular to the stacking direction, and to fix the position of the battery cell in the stacking direction.

[0049] Taking the stacking direction of the flow battery stack as the Z direction and the plane perpendicular to the Z direction as the XY plane, it can be understood that the frame 10 fixes the battery unit in the XY direction to prevent the battery unit from moving in the lateral direction of the flow battery stack. In addition, the frame 10 can also fix the position of the battery unit located in the mounting position 101 in the Z direction to prevent the battery unit from moving in the Z direction.

[0050] According to the law of resistance, the resistance of a conductor is directly proportional to its length and inversely proportional to its cross-sectional area. To suppress shunt current in the battery stack, the spiral flow channel 201 needs to have sufficient length. In some embodiments, the length of the spiral flow channel 201 is greater than 1000 mm. It should be noted that the length of the spiral flow channel 201 mentioned here does not include the length of the liquid circuit connector.

[0051] In some embodiments, the length of the spiral flow channel 201 is greater than 1200 mm. By using a spiral flow channel 201 with a length greater than 1 meter, the flow path of the electrolyte is increased, thereby increasing the resistance of the electrolyte between each battery cell and reducing the parasitic current between each battery cell.

[0052] Specifically, the length of the spiral flow channel 201 is greater than or equal to 1220 mm and less than or equal to 1250 mm. By setting the flow channel to a spiral shape, the area of ​​the guide plate 20 is reduced, allowing an external flow channel of more than 1.2 meters to be integrated into the guide plate 20 with an outer diameter of only about 141 mm, thereby reducing the overall volume of the battery stack.

[0053] To suppress shunt current in the battery stack, the spiral channel 201 also needs to have a small cross-sectional area, thus imposing requirements on the upper limits of its width and height. However, if the cross-sectional area of ​​the spiral channel is too small, it will lead to excessive pressure drop in the high-voltage battery pack, thereby reducing the efficiency of the entire system. In some embodiments, the width of the spiral channel 201 is 4.0 mm to 10.0 mm, and the height of the spiral channel 201 is 1.5 mm to 5.0 mm.

[0054] The width and height of the spiral channel 201 provided in this embodiment ensure that the electrolyte can flow smoothly through the spiral channel 201 at a high velocity, while only causing a slight increase in pump resistance, which is within an acceptable range. Specifically, the width of the spiral channel 201 is 6.5 mm and the height is 2.5 mm. In this case, the thickness of the liquid flow spacer 202 can be 3.5 mm, and the spiral channel 201 and the liquid flow spacer 202 together form a radial pitch s of 10 mm, that is, s = 6.5 mm + 3.5 mm.

[0055] In some embodiments, the inner circumference of the flow frame is circular, and the inner circumference diameter d is 65.0 mm, so that a sufficient volume of electrolyte can pass through the manifold. Then, the number of turns n of the spiral flow channel 201 can be determined by the following formula:

[0056] Where d represents the inner circumferential diameter, s represents the radial pitch of the helix, and L represents the helix length. Based on this relationship, the helical flow channel 201 is wound with 3 to 5 turns. In some embodiments, the helical flow channel 201 is wound with 3.8 turns.

[0057] It should be noted that the above formula does not constitute a limitation on the spiral flow channel 201 in the embodiments of this application. The guide plate 20 and the spiral flow channel 201 can also be other shapes. For example, the inner circumference of the guide plate 20 can be elliptical. Of course, it is not limited to this and is not limited here.

[0058] This application also provides a flow battery stack, which is composed of multiple battery components stacked together. Each battery component includes a battery cell and a flow frame as described in any one of the embodiments of this application.

[0059] In this system, the bipolar plates of the battery cell are installed in the mounting positions of the flow frame, and electrodes of different polarities are respectively arranged on both sides of the bipolar plates. Together with other necessary structures, they constitute the battery cell. The battery cell and the flow frame together constitute the battery assembly, and multiple battery assemblies are stacked to form the flow battery stack.

[0060] In some embodiments, the guide plate has a first surface and a second surface that are opposite to and perpendicular to the thickness direction. The liquid flow spacer is disposed on the first surface and forms a limiting groove. The guide plate forms a limiting protrusion on the second surface. The limiting protrusion of one of the two adjacent guide plates abuts against the limiting groove of the other guide plate.

[0061] In some embodiments, the liquid flow port includes a first liquid flow port and a second liquid flow port, one of which is formed with a docking hole. The docking hole is used to dock with the flow channel opening of the electrolyte flow channel of the battery cell, so that the electrolyte in the guide plate enters the electrolyte flow channel from the docking hole through the flow channel opening, or the electrolyte in the electrolyte flow channel enters the guide plate from the flow channel opening through the docking hole. The wall of either the first or the second fluid flow port is closed, and the first and second fluid flow ports are connected to form a fluid flow connector having the mating hole.

[0062] In some embodiments, the inner circumference of the flow guide disk forms a hollow manifold through hole, and the manifold through holes of the plurality of flow guide disks constitute a manifold channel for accommodating the manifold, the manifold passing through the manifold channel through the stacking direction of the flow battery stack.

[0063] In some embodiments, the first length of the fluid flow frame in the stacking direction is less than or equal to the second length of the battery cell in the stacking direction.

[0064] In some embodiments, the flow frame is made of plastic raw material by injection molding, the plastic raw material including at least one of the following: polyethylene and polypropylene.

[0065] In some embodiments, the flow guide plate is disposed between the first vertex of the frame and the second vertex of the mounting position.

[0066] In some embodiments, the fluid flow port of the fluid flow frame is exposed at the mounting position.

[0067] In some embodiments, the frame is used to fix the battery cell in a plane perpendicular to the stacking direction, and to fix the position of the battery cell in the stacking direction.

[0068] In some embodiments, the length of the spiral channel is greater than 1000 mm.

[0069] In some embodiments, the width of the spiral channel is 4.0 mm to 10.0 mm, and the height of the spiral channel is 1.5 mm to 5.0 mm.

[0070] The specific structure of the flow battery stack provided in this application embodiment can be referred to the specific structure of the flow frame described in any one of the embodiments of this application, and will not be repeated here.

[0071] It should be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application.

[0072] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this invention, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.

[0073] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below,” “under,” or “below” other elements or features will be oriented “above” other elements or features. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0074] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0075] The above description is merely a specific embodiment 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 scope of the technology disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application.

Claims

1. A flow battery stack, characterized in that, The flow battery stack is composed of multiple battery modules stacked together. Each battery module includes a battery cell and a flow frame. The flow frame includes: A frame having mounting positions for mounting the bipolar plates of the battery unit; A flow guide plate is disposed around the mounting position on the frame. The flow guide plate forms a spiral flow channel, which is spaced apart by liquid flow spacers. The liquid flow spacers extend spirally between the outer and inner circumferences of the flow guide plate. The outer periphery of the flow guide plate has a liquid flow port communicating with the spiral flow channel. The liquid flow port is connected to the electrolyte flow channel in the battery cell for electrochemical reactions, so that the electrolyte in the flow guide plate enters the electrolyte flow channel through the liquid flow port, or the electrolyte in the electrolyte flow channel enters the flow guide plate through the liquid flow port. The liquid flow spacer has a liquid flow opening on the inner periphery of the flow guide plate communicating with the spiral flow channel. The liquid flow opening is connected to a manifold, so that the electrolyte in the manifold enters the flow guide plate through the liquid flow opening, or the electrolyte in the flow guide plate enters the manifold through the liquid flow opening. The manifold is connected to the liquid storage tank of the flow battery. The guide plate has a first surface and a second surface that are opposite to and perpendicular to the thickness direction. The liquid flow spacer is disposed on the first surface and forms a limiting groove. The guide plate forms a limiting protrusion on the second surface. The limiting protrusion of one of the two adjacent guide plates abuts against the limiting groove of the other guide plate. The liquid flow port includes a first liquid flow port and a second liquid flow port. One of the first liquid flow port and the second liquid flow port is formed with a docking hole. The docking hole is used to dock with the flow channel opening of the electrolyte flow channel of the battery cell, so that the electrolyte in the guide plate enters the electrolyte flow channel from the docking hole through the flow channel opening, or the electrolyte in the electrolyte flow channel enters the guide plate from the flow channel opening through the docking hole. The wall of the first liquid flow port or the second liquid flow port is enclosed, and the first liquid flow port and the second liquid flow port are connected to form a liquid flow connector with the mating hole.

2. The flow battery stack according to claim 1, characterized in that, The inner circumference of the flow guide plate forms a hollow manifold through hole, and the manifold through holes of the multiple flow guide plates constitute a manifold channel for accommodating the manifold. The manifold passes through the manifold channel in the stacking direction of the flow battery stack.

3. The flow battery stack according to claim 1, characterized in that, The first length of the fluid flow frame in the stacking direction is less than or equal to the second length of the battery cell in the stacking direction.

4. The flow battery stack according to claim 1, characterized in that, The fluid flow frame is made of plastic raw material by injection molding, and the plastic raw material includes at least one of the following: polyethylene and polypropylene.

5. The flow battery stack according to claim 1, characterized in that, The flow guide plate is positioned between the first vertex of the frame and the second vertex of the mounting position.

6. The flow battery stack according to claim 1, characterized in that, The fluid flow port of the fluid flow frame is exposed at the mounting position.

7. The flow battery stack according to any one of claims 1 to 6, characterized in that, The frame is used to fix the battery unit on a plane perpendicular to the stacking direction, and to fix the position of the battery unit in the stacking direction.

8. The flow battery stack according to any one of claims 1 to 6, characterized in that, The length of the spiral flow channel is greater than 1000 mm.

9. The flow battery stack according to any one of claims 1 to 6, characterized in that, The width of the spiral channel is 4.0mm to 10.0mm, and the height of the spiral channel is 1.5mm to 5.0mm.

10. A fluid flow frame, characterized in that, The fluid flow frame includes: A frame having mounting positions for mounting the bipolar plates of a battery cell; A flow guide plate is disposed around the mounting position on the frame. The flow guide plate forms a spiral flow channel, which is spaced apart by liquid flow spacers. The liquid flow spacers extend spirally between the outer and inner circumferences of the flow guide plate. The outer periphery of the flow guide plate has a liquid flow port communicating with the spiral flow channel. The liquid flow port is connected to the electrolyte flow channel in the battery cell for electrochemical reactions, so that the electrolyte in the flow guide plate enters the electrolyte flow channel through the liquid flow port, or the electrolyte in the electrolyte flow channel enters the flow guide plate through the liquid flow port. The liquid flow spacer has a liquid flow opening on the inner periphery of the flow guide plate communicating with the spiral flow channel. The liquid flow opening is connected to a manifold, so that the electrolyte in the manifold enters the flow guide plate through the liquid flow opening, or the electrolyte in the flow guide plate enters the manifold through the liquid flow opening. The manifold is connected to the liquid storage tank of the flow battery. The guide plate has a first surface and a second surface that are opposite to and perpendicular to the thickness direction. The liquid flow spacer is disposed on the first surface and forms a limiting groove. The guide plate forms a limiting protrusion on the second surface. The limiting protrusion of one of the two adjacent guide plates abuts against the limiting groove of the other guide plate. The liquid flow port includes a first liquid flow port and a second liquid flow port. One of the first liquid flow port and the second liquid flow port is formed with a docking hole. The docking hole is used to dock with the flow channel opening of the electrolyte flow channel of the battery cell, so that the electrolyte in the guide plate enters the electrolyte flow channel from the docking hole through the flow channel opening, or the electrolyte in the electrolyte flow channel enters the guide plate from the flow channel opening through the docking hole. The wall of the first liquid flow port or the second liquid flow port is enclosed, and the first liquid flow port and the second liquid flow port are connected to form a liquid flow connector with the mating hole.

11. The fluid flow frame according to claim 10, characterized in that, The inner circumference of the guide plate forms a hollow manifold through hole, and the manifold through holes of the multiple guide plates constitute a manifold channel for accommodating the manifold. The manifold passes through the guide plates of the multiple liquid flow frames via the manifold channel.

12. The fluid flow frame according to claim 10, characterized in that, The first length of the fluid flow frame in the stacking direction is less than or equal to the second length of the battery cell in the stacking direction.

13. The fluid flow frame according to claim 10, characterized in that, The fluid flow frame is made of plastic raw material by injection molding, and the plastic raw material includes at least one of the following: polyethylene and polypropylene.

14. The fluid flow frame according to claim 10, characterized in that, The flow guide plate is positioned between the first vertex of the frame and the second vertex of the mounting position.

15. The fluid flow frame according to claim 10, characterized in that, The fluid flow port of the fluid flow frame is exposed at the mounting position.

16. The fluid flow frame according to any one of claims 10 to 15, characterized in that, The frame is used to fix the battery unit on a plane perpendicular to the stacking direction, and to fix the position of the battery unit in the stacking direction.

17. The fluid flow frame according to any one of claims 10 to 15, characterized in that, The length of the spiral flow channel is greater than 1000 mm.

18. The fluid flow frame according to any one of claims 10 to 15, characterized in that, The width of the spiral channel is 4.0mm to 10.0mm, and the height of the spiral channel is 1.5mm to 5.0mm.

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