Flow battery electric pile structure based on multi-channel and multi-layer cross flow channel and control method of flow battery electric pile structure

Abstract

The invention discloses a flow battery stack structure based on multi-channel and multi-layer cross flow channels and a control method thereof, the flow battery stack structure comprises single stack assemblies which are connected in series, two collector plates are respectively arranged on two sides of the plurality of single stack assemblies, two end plates are respectively arranged on the outer sides of the two collector plates, and the two end plates are respectively arranged on the outer sides of the two collector plates. Each single electric pile assembly comprises an electrode frame, bipolar plates, an electrode plate and an ion exchange membrane, and a multi-channel and multi-layer cross flow channel for uniform circulation of an electrolyte is formed between the bipolar plates and the electrode plates. The first bipolar plate, the second bipolar plate and the third bipolar plate are provided with transverse flow channels, longitudinal flow channels and cross flow channels; the electrode plates are mutually overlapped to form a multi-channel and multi-layer cross flow channel, so that the electrolyte is fully mixed and circulated in the multi-channel and multi-layer cross flow channel, and the concentric-square-shaped flow channels and the flow guide cavities on the electrode plates generate a concentric-square-shaped turbulent flow effect, so that the electrolyte and active substances are fully mixed and reacted, the electrolyte can be uniformly distributed, the concentration of the electrolyte is stable, and the reaction efficiency of the flow battery is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of flow battery stacks, and particularly relates to a flow battery stack structure based on multi-channel multi-layer cross-flow channels and a control method therefor. Background Art

[0002] A flow battery is an energy storage technology that realizes energy storage and release through the cyclic flow of liquid electrolytes in a stack, and the stack structure directly affects the energy efficiency, power density, and cycle life of the battery.

[0003] Existing flow battery stack structures mostly adopt single flow channels, such as serpentine flow channels, parallel flow channels, etc. Single flow channels are prone to causing local electrolyte concentration difference polarization, resulting in uneven electrolyte distribution, and further leading to insufficient reaction of active substances, affecting the reaction efficiency of flow batteries. For this reason, we propose a flow battery stack structure based on multi-channel multi-layer cross-flow channels and a control method therefor. Summary of the Invention

[0004] The purpose of the present invention is to provide a flow battery stack structure based on multi-channel multi-layer cross-flow channels and a control method therefor, so as to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A flow battery stack structure based on multi-channel multi-layer cross-flow channels, including, Single stack components, which are provided with several and are connected in series; Current collector plates, which are provided with two, and the two current collector plates are respectively arranged on both sides of several single stack components; End plates, which are provided with two, and the two end plates are respectively arranged outside the two current collector plates; Wherein, the single stack component includes an electrode frame, a bipolar plate, an electrode plate, and an ion exchange membrane; The bipolar plate is arranged inside the electrode frame, and the electrode frame, the bipolar plate, and the electrode plate are all provided with two, and are symmetrically distributed with respect to the ion exchange membrane; A multi-channel multi-layer cross-flow channel for uniform circulation of electrolyte is formed between the bipolar plate and the electrode plate.

[0006] Preferably, the two end plates are locked and fixed by fixing screws and locking nuts, and the current collector plates and the single stack components between the two end plates are fixedly connected.

[0007] Preferably, the single stack components, the current collector plates, and the end plates are all hermetically connected through sealing members.

[0008] Preferably, the electrode frame, the bipolar plate, the electrode plate and the ion exchange membrane are all hermetically connected through seals.

[0009] Preferably, an electrolyte inlet and an electrolyte outlet are provided on the end plate, and the electrolyte inlet and the electrolyte outlet are respectively connected to the output end and the input end of the electrolyte tank.

[0010] Preferably, the two current collector plates are respectively connected to the positive and negative electrodes of the power supply, and a current collection cavity is formed on one side of the current collector plate facing the electrode frame, and the electrolyte inlet and the electrolyte outlet are both communicated with the current collection cavity.

[0011] Preferably, a bipolar plate installation card slot is formed on the electrode frame, and the bipolar plate is installed in the bipolar plate installation card slot; The bipolar plate includes a first bipolar plate, a second bipolar plate and a third bipolar plate, and the first bipolar plate, the second bipolar plate and the third bipolar plate are connected in sequence; Through holes arranged in a rectangular array are formed on the first bipolar plate, the second bipolar plate and the third bipolar plate, and the through holes are communicated with the current collection cavity. A transverse flow channel distributed horizontally is formed at a position corresponding to the through holes arranged in a rectangular array on one side of the first bipolar plate facing the second bipolar plate. A longitudinal flow channel distributed longitudinally is formed at a position corresponding to the through holes arranged in a rectangular array on one side of the second bipolar plate facing the third bipolar plate. An obliquely crossed flow channel is formed at a position corresponding to the through holes arranged in a rectangular array on one side of the third bipolar plate facing the electrode plate; The transverse flow channel on the first bipolar plate, the longitudinal flow channel on the second bipolar plate and the crossed flow channel on the third bipolar plate form a multi-channel multi-layer crossed flow channel.

[0012] Preferably, the through hole has an arc-shaped shrinking structure along the electrolyte input direction.

[0013] Preferably, a return flow channel is formed at a position corresponding to the crossed flow channel on one side of the electrode plate facing the third bipolar plate. Diffusion holes are uniformly distributed on one side of the electrode plate facing the ion exchange membrane. A diversion cavity is formed inside the electrode plate, and the return flow channel and the diffusion holes are both communicated with the diversion cavity.

[0014] A control method for a flow battery stack structure based on a multi-channel multi-layer crossed flow channel includes the following steps: A. Electrolyte pumping: The electrolyte is pumped from the electrolyte tank into the electrolyte inlet through a pump, and then the whole is collected and flows into the current collection cavity in the current collector plate; B. Uniform diffusion and transportation of the electrolyte: The electrolyte in the current collector cavity is guided to the bipolar plates on the electrode frame. First, it enters the transverse flow channel through the through holes on the first bipolar plate, then enters the through holes on the second bipolar plate from the transverse flow channel, then enters the longitudinal flow channel, and finally enters the cross flow channel through the through holes on the third bipolar plate. During this process, the multi-channel multi-layer cross flow channel enables the electrolyte to uniformly diffuse towards the electrode plate; C. Electrolyte loop turbulence: The electrolyte enters the diversion cavity together through the loop channels on the electrode plate, and a loop turbulence effect is formed in the diversion cavity, enabling the electrolyte to fully mix and react. Then, it is discharged through the diffusion holes on the electrode plate and ion exchange occurs through the ion exchange membrane.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. In the present invention, the first bipolar plate, the second bipolar plate, and the third bipolar plate form a multi-layer structure, and transverse flow channels, longitudinal flow channels, and cross flow channels are provided on the first bipolar plate, the second bipolar plate, and the third bipolar plate, and are superimposed on each other to form a multi-channel multi-layer cross flow channel, enabling the electrolyte to fully mix and flow in the multi-channel multi-layer cross flow channel, and generating a loop turbulence effect in the loop channels and the diversion cavity on the electrode plate, further enabling the electrolyte and the active substance to fully mix and react. By using flow channels of various shapes in cooperation, the electrolyte distribution can be made uniform, the electrolyte concentration can be stabilized, and the reaction efficiency of the flow battery can be improved; 2. In the present invention, the through holes are in an arc-shaped narrowing structure along the electrolyte input direction, increasing the conveying pressure when the electrolyte passes through the through holes, thereby accelerating the conveying speed of the electrode liquid, and further enabling the turbulence mixing when the electrolyte is conveyed between the first bipolar plate, the second bipolar plate, and the third bipolar plate, so that the electrolyte is fully mixed and distributed. Description of the Drawings

[0016] Figure 1 It is a schematic three-dimensional structure diagram of the whole of the present invention; Figure 2 It is a schematic three-dimensional structure diagram of the whole of the present invention; Figure 3 It is a schematic front sectional structure diagram of the present invention; Figure 4 It is a schematic three-dimensional structure diagram of the current collector plate and the end plate of the present invention; Figure 5 It is a schematic three-dimensional structure diagram of the single cell stack assembly of the present invention; Figure 6 It is a schematic three-dimensional structure diagram of the electrode frame and the bipolar plate of the present invention; Figure 7 It is a schematic three-dimensional structure diagram of the electrode frame and the bipolar plate of the present invention; Figure 8 It is a schematic three-dimensional structure diagram of the bipolar plate of the present invention; Figure 9Schematic three-dimensional structure diagram of the bipolar plate of the present invention; Figure 10 Schematic three-dimensional structure diagram of the first bipolar plate of the present invention; Figure 11 Schematic three-dimensional structure diagram of the second bipolar plate of the present invention; Figure 12 Schematic three-dimensional structure diagram of the third bipolar plate of the present invention; Figure 13 Schematic three-dimensional structure diagram of the electrode plate of the present invention; Figure 14 Schematic cross-sectional structure diagram of the electrode plate of the present invention.

[0017] In the figure: 1. Single stack assembly; 101. Electrode frame; 102. Bipolar plate; 1021. First bipolar plate; 1022. Second bipolar plate; 1023. Third bipolar plate; 103. Electrode plate; 104. Ion exchange membrane; 105. Bipolar plate installation card slot; 106. Through hole; 107. Transverse flow channel; 108. Longitudinal flow channel; 109. Cross flow channel; 110. Meandering flow channel; 111. Diffusion hole; 112. Diversion cavity; 2. Current collector plate; 201. Current collection cavity; 3. End plate; 301. Electrolyte inlet; 302. Electrolyte outlet; 4. Fixed screw; 5. Locking nut. Detailed implementation manners

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0019] Please refer to Figures 1-14 , the flow battery stack structure based on a multi-channel multi-layer cross flow channel provided by the present invention includes A single stack assembly 1, which is provided with several and is connected in series; Two current collector plates 2, which are respectively arranged on both sides of several single stack assemblies 1. The two current collector plates 2 are respectively connected to the positive and negative electrodes of the power supply, and a current collection cavity 201 is opened on the side of the current collector plate 2 facing the electrode frame 101. The electrolyte inlet 301 and the electrolyte outlet 302 are both connected to the current collection cavity 201; End plates 3, there are two of them. The two end plates 3 are respectively arranged on the outer sides of the two current collector plates 2. The two end plates 3 are locked and fixed through fixing screws 4 and lock nuts 5, so as to fixedly connect the current collector plate 2 and the single fuel cell stack assembly 1 between the two end plates 3. An electrolyte inlet 301 and an electrolyte outlet 302 are arranged on the end plate 3. The electrolyte inlet 301 and the electrolyte outlet 302 are respectively connected to the output end and the input end of the electrolyte tank; Among them, the single fuel cell stack assembly 1 includes an electrode frame 101, a bipolar plate 102, an electrode plate 103 and an ion exchange membrane 104; The bipolar plate 102 is arranged inside the electrode frame 101. There are two of the electrode frame 101, the bipolar plate 102 and the electrode plate 103, and they are all symmetrically distributed with respect to the ion exchange membrane 104; A multi-channel multi-layer cross flow channel for the uniform flow of the electrolyte is formed between the bipolar plate 102 and the electrode plate 103; A bipolar plate installation slot 105 is formed on the electrode frame 101, and the bipolar plate 102 is installed in the bipolar plate installation slot 105; the bipolar plate 102 includes a first bipolar plate 1021, a second bipolar plate 1022 and a third bipolar plate 1023, and the first bipolar plate 1021, the second bipolar plate 1022 and the third bipolar plate 1023 are connected in sequence; Through holes 106 distributed in a rectangular array are formed on the first bipolar plate 1021, the second bipolar plate 1022 and the third bipolar plate 1023. The through holes 106 are communicated with the current collector cavity 201. A transverse flow channel 107 distributed horizontally is formed at the position corresponding to the through holes 106 distributed in a rectangular array on the side of the first bipolar plate 1021 facing the second bipolar plate 1022. A longitudinal flow channel 108 distributed longitudinally is formed at the position corresponding to the through holes 106 distributed in a rectangular array on the side of the second bipolar plate 1022 facing the third bipolar plate 1023. An obliquely cross-distributed cross flow channel 109 is formed at the position corresponding to the through holes 106 distributed in a rectangular array on the side of the third bipolar plate 1023 facing the electrode plate 103; the transverse flow channel 107 on the first bipolar plate 1021, the longitudinal flow channel 108 on the second bipolar plate 1022 and the cross flow channel 109 on the third bipolar plate 1023 form a multi-channel multi-layer cross flow channel; A return flow channel 110 is formed at the position corresponding to the cross flow channel 109 on the side of the electrode plate 103 facing the third bipolar plate 1023. Uniformly distributed diffusion holes 111 are formed on the side of the electrode plate 103 facing the ion exchange membrane 104. A diversion cavity 112 is formed inside the electrode plate 103. The return flow channel 110 and the diffusion holes 111 are both communicated with the diversion cavity 112.

[0020] In the present invention, a multi-layer structure is formed by the first bipolar plate 1021, the second bipolar plate 1022 and the third bipolar plate 1023. Transverse flow channels 107, longitudinal flow channels 108 and cross flow channels 109 are arranged on the first bipolar plate 1021, the second bipolar plate 1022 and the third bipolar plate 1023, and are superimposed on each other to form a multi-channel multi-layer cross flow channel, enabling the electrolyte to fully mix and flow in the multi-channel multi-layer cross flow channel, and generating a loop turbulence effect in the loop flow channel 110 and the diversion cavity 112 on the electrode plate 103, further enabling the electrolyte and the active material to fully mix and react. By cooperating with each other using flow channels of various shapes, the electrolyte distribution can be made uniform, the electrolyte concentration can be stabilized, and the reaction efficiency of the flow battery can be improved; In this embodiment, the single cell stack assembly 1, the current collector plate 2 and the end plate 3 are all hermetically connected through seals. The electrode frame 101, the bipolar plate 102, the electrode plate 103 and the ion exchange membrane 104 are all hermetically connected through seals, improving the connection tightness of the flow battery stack and avoiding the problem of electrolyte leakage.

[0021] In this embodiment, as Figure 5 and Figure 6 shown, the through hole 106 is a structure that gradually shrinks in an arc shape along the electrolyte input direction, increasing the conveying pressure when the electrolyte passes through the through hole 106, thereby accelerating the conveying speed of the electrode liquid, and further causing turbulent mixing when the electrolyte is conveyed between the first bipolar plate 1021, the second bipolar plate 1022 and the third bipolar plate 1023, so that the electrolyte is fully mixed and distributed.

[0022] The control method for the flow battery stack structure based on the multi-channel multi-layer cross flow channel provided by the present invention includes the following steps: A. Electrolyte pumping: The electrolyte is pumped from the electrolyte tank into the electrolyte inlet 301 through a pump, and then integrally collects and enters the current collection cavity 201 in the current collector plate 2; B. Uniform diffusion and transportation of the electrolyte: The electrolyte in the current collection cavity 201 is diverted to the bipolar plate 102 on the electrode frame 101. First, it enters the transverse flow channel 107 through the through hole 106 on the first bipolar plate 1021, then enters the through hole 106 on the second bipolar plate 1022 from the transverse flow channel 107, then enters the longitudinal flow channel 108, and finally enters the cross flow channel 109 through the through hole 106 on the third bipolar plate 1023. During this process, the multi-channel multi-layer cross flow channel enables the electrolyte to uniformly diffuse towards the electrode plate 103; C. Loop turbulence of the electrolyte: The electrolyte enters the diversion cavity 112 together through the loop flow channel 110 on the electrode plate 103, and a loop turbulence effect is formed in the diversion cavity 112, enabling the electrolyte to fully mix and react, and then is discharged through the diffusion hole 111 on the electrode plate 103 and performs ion exchange through the ion exchange membrane 104.

[0023] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A flow battery stack structure based on a multi-channel multi-layer cross-flow channel, characterized in that, including, a single fuel cell stack assembly (1), with several of them provided and connected in series; current collector plates (2), with two of them provided, and the two current collector plates (2) are respectively arranged on both sides of the several single fuel cell stack assemblies (1); end plates (3), with two of them provided, and the two end plates (3) are respectively arranged on the outer sides of the two current collector plates (2); wherein, the single fuel cell stack assembly (1) includes an electrode frame (101), a bipolar plate (102), an electrode plate (103) and an ion exchange membrane (104); the bipolar plate (102) is arranged inside the electrode frame (101), and there are two of the electrode frame (101), the bipolar plate (102) and the electrode plate (103), and they are symmetrically distributed with respect to the ion exchange membrane (104); a multi-channel multi-layer cross flow channel for uniform flow of electrolyte is formed between the bipolar plate (102) and the electrode plate (103).

2. The structure of a flow battery stack based on a multi-channel multi-layer cross-flow channel according to claim 1, characterized in that: The two end plates (3) are locked and fixed by fixing screws (4) and locking nuts (5), and the current collector plate (2) and the single fuel cell stack assembly (1) between the two end plates (3) are fixedly connected.

3. A flow battery stack structure based on a multi-channel multi-layer cross-flow channel according to claim 1, characterized in that: The single fuel cell stack assembly (1), the current collector plate (2) and the end plate (3) are all hermetically connected by seals.

4. A flow battery stack structure based on a multi-channel multi-layer cross-flow channel according to claim 1, characterized in that: The electrode frame (101), the bipolar plate (102), the electrode plate (103) and the ion exchange membrane (104) are all hermetically connected by seals.

5. A flow battery stack structure based on a multi-channel multi-layer cross-flow channel according to claim 1, characterized in that: An electrolyte inlet (301) and an electrolyte outlet (302) are arranged on the end plate (3), and the electrolyte inlet (301) and the electrolyte outlet (302) are respectively connected to the output end and the input end of an electrolyte tank.

6. The structure of a flow battery stack based on a multi-channel multi-layer cross-flow channel according to claim 1, characterized in that: The two current collector plates (2) are respectively connected to the positive and negative electrodes of a power supply, and a current collection cavity (201) is formed on one side of the current collector plate (2) facing the electrode frame (101), and the electrolyte inlet (301) and the electrolyte outlet (302) are both communicated with the current collection cavity (201).

7. A flow battery stack structure based on a multi-channel multi-layer cross-flow channel according to claim 1, wherein: A bipolar plate installation card slot (105) is formed on the electrode frame (101), and the bipolar plate (102) is installed in the bipolar plate installation card slot (105); The bipolar plate (102) includes a first bipolar plate (1021), a second bipolar plate (1022) and a third bipolar plate (1023), and the first bipolar plate (1021), the second bipolar plate (1022) and the third bipolar plate (1023) are connected in sequence; The first bipolar plate (1021), the second bipolar plate (1022), and the third bipolar plate (1023) are each provided with through holes (106) distributed in a rectangular array. The through holes (106) communicate with the current collecting chamber (201). On the side of the first bipolar plate (1021) facing the second bipolar plate (1022), transverse flow channels (107) are provided at positions corresponding to the through holes (106) distributed in a rectangular array and are distributed horizontally. On the side of the second bipolar plate (1022) facing the third bipolar plate (1023), longitudinal flow channels (108) are provided at positions corresponding to the through holes (106) distributed in a rectangular array and are distributed longitudinally. On the side of the third bipolar plate (1023) facing the electrode plate (103), cross flow channels (109) are provided at positions corresponding to the through holes (106) distributed in a rectangular array and are distributed in an oblique cross pattern; The transverse flow channels (107) on the first bipolar plate (1021), the longitudinal flow channels (108) on the second bipolar plate (1022), and the cross flow channels (109) on the third bipolar plate (1023) form a multi-channel multi-layer cross flow channel.

8. A flow battery stack structure based on a multi-channel multi-layer cross-flow channel according to claim 7, characterized in that: The through holes (106) are of an arc-shaped shrinking structure along the electrolyte input direction.

9. The structure of a flow battery stack based on a multi-channel multi-layer cross-flow channel according to claim 8, characterized in that: On the side of the electrode plate (103) facing the third bipolar plate (1023), a return flow channel (110) is provided at a position corresponding to the cross flow channel (109). On the side of the electrode plate (103) facing the ion exchange membrane (104), diffusion holes (111) are provided in a uniform distribution. A diversion chamber (112) is provided inside the electrode plate (103). The return flow channel (110) and the diffusion holes (111) both communicate with the diversion chamber (112).

10. A control method for a flow battery stack structure based on a multi-channel multi-layer cross-flow channel according to any one of claims 1-9, characterized in that, It includes the following steps: A. Electrolyte pumping: The electrolyte is pumped from the electrolyte tank through a pump into the electrolyte inlet (301), and then the whole is collected and flows into the current collecting chamber (201) in the current collecting plate (2); B. Uniform diffusion and transportation of the electrolyte: The electrolyte in the current collecting chamber (201) is diverted to the bipolar plates (102) on the electrode frame (101). First, it enters the transverse flow channels (107) through the through holes (106) on the first bipolar plate (1021), then enters the through holes (106) on the second bipolar plate (1022) from the transverse flow channels (107), then enters the longitudinal flow channels (108), and finally enters the cross flow channels (109) through the through holes (106) on the third bipolar plate (1023). During this process, the multi-channel multi-layer cross flow channel enables the electrolyte to be uniformly diffused towards the electrode plate (103); C. Return-shaped turbulent flow of the electrolyte: The electrolyte enters the diversion chamber (112) together with the return flow channel (110) on the electrode plate (103), and a return-shaped turbulent flow effect is formed in the diversion chamber (112) to enable the electrolyte to be fully mixed and react, and then it is discharged through the diffusion holes (111) on the electrode plate (103) and ion exchange is carried out through the ion exchange membrane (104).

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