A flow battery electrode frame assembly and battery cell

Abstract

The application relates to the technical field of liquid flow batteries, in particular to a liquid flow battery electrode frame assembly and a battery unit, which comprises a female frame, a public flow channel is formed in the female frame, an internal flow channel group and an electrode cavity are respectively formed in the female frame, the internal flow channel group is respectively communicated with the public flow channel and the electrode cavity, when two adjacent female frames are pasted face to face, the internal flow channel groups on the two female frames are overlapped and communicated in the thickness direction of the female frame, and the public flow channels on the two female frames are communicated; a sub-frame is arranged on the female frame; a bipolar plate is arranged between the sub-frame and the female frame. The application has the effect of increasing the flow channel depth in the limited electrode frame thickness.

Description

Technical Field

[0001] This application relates to the technical field of flow batteries, and in particular to a flow battery electrode frame assembly and battery cell. Background Technology

[0002] Currently, flow batteries are a large-scale energy storage technology with advantages such as high capacity, long lifespan, and good safety. Their core component, the fuel cell stack, is composed of multiple stacked battery cells. Each battery cell typically includes an electrode frame, carbon felt electrodes, bipolar plates, and an ion exchange membrane. To improve the volumetric power density and reduce the cost of flow batteries, a key technological iteration direction in the industry is "increasing current density and thinning the carbon felt electrodes." That is, by using thinner carbon felt electrodes and arranging more active material within a limited volume, the overall power output of the fuel cell stack can be increased.

[0003] However, this technical approach of "thinning the carbon felt and improving electrical density" has led to a specific technical problem in practice: to match the thinned carbon felt, the thickness of the electrode frame must also be reduced accordingly. This directly results in insufficient depth of the flow channels inside the electrode frame for electrolyte flow. The reduction in channel depth has two significant negative impacts: First, the smaller cross-sectional area of ​​the flow channel significantly increases the electrolyte flow resistance (flow resistance), increasing pumping losses and reducing system efficiency; second, the enhanced wall effect within the shallow channel leads to uneven electrolyte velocity distribution across the channel cross-section, resulting in inconsistent electrolyte flow distribution within the reaction area, affecting the uniformity of the electrochemical reaction, and potentially causing localized overheating, increased side reactions, and ultimately damaging battery performance and lifespan.

[0004] Therefore, existing technologies face a prominent contradiction: they need to adapt to high-performance thin carbon felt by thinning the electrode frame, while ensuring sufficient flow channel depth to maintain low flow resistance and uniform flow distribution. How to effectively increase the flow channel depth without increasing the overall thickness of the electrode frame (i.e., without deviating from the original intention of thin electrode design) has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] In order to increase the flow channel depth within a limited electrode frame thickness, this application provides a flow battery electrode frame assembly and battery cell.

[0006] In a first aspect, the flow battery electrode frame assembly provided in this application adopts the following technical solution:

[0007] A flow battery electrode frame assembly, comprising:

[0008] A mother frame, on which a common flow channel is formed, and on which internal flow channel groups and electrode cavities are formed respectively, the internal flow channel groups are connected to the common flow channel and the electrode cavities respectively. When two adjacent mother frames are placed face to face, the internal flow channel groups on the two mother frames overlap and connect in the thickness direction of the mother frame, and the common flow channel on the two mother frames is connected.

[0009] The sub-frame is set on the parent frame;

[0010] A bipolar plate is disposed between the sub-frame and the mother frame.

[0011] By adopting the above technical solution, the internal flow channel groups and common flow channels on the two mother frames overlap and connect when adjacent mother frames are face to face, allowing the electrolyte to flow smoothly between multiple mother frames. This increases the flow channel depth within the limited electrode frame thickness, expands the electrolyte flow path and space, avoids the problem of insufficient flow channel depth in a single mother frame, effectively reduces wall effect, lowers flow resistance, and improves the uniformity of flow distribution. The number of sub-frames is equal to that of the mother frames and they are set one-to-one. The bipolar plates are set between the sub-frames and the mother frames, ensuring the integrity and stability of the electrode frame assembly structure. This allows the electrode frame assembly to better play its role in the flow battery, improving the overall performance and reliability of the flow battery.

[0012] Optionally, the common flow channel includes a positive electrode inlet, a negative electrode inlet, a positive electrode outlet, and a negative electrode outlet respectively disposed on the mother frame. The internal flow channel group is provided in two sets, which are symmetrically arranged along the electrode cavity. The positive electrode inlet and the negative electrode inlet are respectively connected to one set of the internal flow channel group, and the positive electrode outlet and the negative electrode outlet are respectively connected to the other set of the internal flow channel group.

[0013] By adopting the above technical solution, two sets of internal flow channel groups are symmetrically arranged along the electrode cavity, and the positive and negative electrode liquid inlets are respectively connected to one set of internal flow channel groups, while the positive and negative electrode liquid outlets are respectively connected to the other set of internal flow channel groups. This symmetrical and correspondingly connected design makes the flow of electrolyte in the electrode frame assembly more orderly and uniform, effectively balancing the electrolyte flow rate and velocity of the positive and negative electrodes, avoiding local reaction differences caused by uneven electrolyte distribution, thereby improving the reaction efficiency and stability of the battery electrodes, and thus improving the performance and service life of the entire flow battery unit.

[0014] Optionally, the internal flow channel group includes a main flow channel, a first blind-end flow channel, a secondary flow channel, and a second blind-end flow channel. One main flow channel and one first blind-end flow channel are respectively connected to the positive electrode inlet, and another main flow channel and another first blind-end flow channel are respectively connected to the negative electrode outlet. One secondary flow channel and one second blind-end flow channel are respectively connected to the negative electrode inlet, and another secondary flow channel and another second blind-end flow channel are respectively connected to the positive electrode outlet. Two guide grooves connected to the electrode cavity are respectively opened on the mother frame. The main flow channel connected to the positive electrode inlet is connected to one of the guide grooves, and the second blind-end flow channel connected to the positive electrode outlet is connected to the other guide groove.

[0015] When two adjacent mother frames are placed face to face, the main flow channel on one mother frame overlaps and connects with the second blind flow channel on the other mother frame, and the secondary flow channel on one mother frame overlaps and connects with the first blind flow channel on the other mother frame.

[0016] By adopting the above technical solution, the internal flow channel assembly includes a main flow channel, a first blind-end flow channel, a secondary flow channel, and a second blind-end flow channel, which are reasonably connected to the positive and negative electrode inlets and outlets. Furthermore, a guide groove is formed on the mother frame, communicating with the electrode cavity, allowing the electrolyte to enter the electrode cavity from the inlet through the corresponding flow channel and guide groove, and then flow out from the electrode cavity through the corresponding flow channel and guide groove, forming a complete electrolyte flow path. When two adjacent mother frames are placed face-to-face, the main flow channel on one mother frame overlaps and connects with the second blind-end flow channel on the other mother frame, and the secondary flow channel on one mother frame overlaps and connects with the first blind-end flow channel on the other mother frame. This expands the flow channel depth in the thickness direction of the mother frame, increasing the effective cross-sectional area of ​​the flow channel. The increased flow channel depth reduces the wall effect, decreasing the resistance encountered by the electrolyte flowing within the channel, thereby reducing flow resistance. Meanwhile, a reasonable flow channel layout and connection method ensure that the electrolyte can be more evenly distributed into the electrode cavity, improving the uniformity of flow distribution, which in turn helps to improve the performance and efficiency of the flow battery.

[0017] Optionally, the main flow channel, the first blind end flow channel, the secondary flow channel, and the second blind end flow channel are all designed in an S-shape or an L-shape.

[0018] By adopting the above technical solution, the main flow channel, the first blind-end flow channel, the secondary flow channel, and the second blind-end flow channel are all designed in an S-shape or L-shape. On the one hand, the curved flow channel shape can increase the flow path length of the electrolyte, allowing the electrolyte to have more residence time in the flow channel and fully contact the electrode, improving the efficiency of the electrode reaction and thus enhancing the battery performance. On the other hand, compared with a straight flow channel, the S-shaped or L-shaped flow channel can better disperse the flow pressure of the electrolyte, reduce local pressure concentration, effectively mitigate the wall effect, and thus reduce flow resistance. It also helps to improve the uniformity of flow distribution, allowing the electrolyte to be more evenly distributed in the electrode cavity, further improving the overall performance and stability of the battery. In addition, the S-shaped flow channel, by significantly extending the flow path of the electrolyte in the flow frame, is equivalent to increasing the length of the bypass current flow path, which significantly increases the resistance of the bypass current flow path, thereby effectively suppressing the intensity of the bypass current and thus effectively reducing the bypass current of the stack, indirectly improving the energy effect of the stack.

[0019] Optionally, a flow-dividing protrusion is provided in the flow guide groove, and an electrolyte distribution area is provided at both ends of the electrode cavity. The electrolyte distribution area is connected to the flow guide groove, and a plurality of protrusions are provided in the electrolyte distribution area. The flow-dividing protrusions and the plurality of protrusions cooperate to ensure the uniformity of electrolyte entering the electrode cavity.

[0020] By adopting the above technical solution, the diversion protrusions installed in the guide channel can initially divert the electrolyte entering the guide channel, allowing the electrolyte to flow to the electrolyte distribution area in a more rational manner. Simultaneously, several protrusions are installed in the electrolyte distribution areas at both ends of the electrode cavity. After the electrolyte undergoes initial diversion and enters the distribution area, the protrusions further block, disperse, and guide the electrolyte. The diversion protrusions and other protrusions work together to ensure that the electrolyte is more evenly distributed throughout the electrode cavity upon entering, thus guaranteeing the uniformity of electrolyte entry into the electrode cavity.

[0021] Optionally, the mother frame has two through holes. One through hole communicates with the first blind end flow channel near the negative electrode outlet, and the other through hole communicates with the secondary flow channel near the negative electrode inlet. The sub-frame also has the electrode cavity and the guide groove. The sub-frame has two sub-frame holes, which pass through the guide groove and communicate with the through holes. The electrode cavity on the sub-frame is correspondingly arranged with the electrode cavity on the mother frame.

[0022] By adopting the above technical solution, when the electrolyte enters the secondary flow channel from the negative electrode inlet, it can enter the electrode cavity of the sub-frame through the perforations and sub-frame holes, providing electrolyte for the electrodes at the sub-frame. At the same time, the electrolyte flowing out from the first blind end flow channel corresponding to the negative electrode outlet can also be reasonably circulated and distributed through the perforations and sub-frame holes, thereby ensuring the effective flow and distribution of electrolyte within the electrode frame assembly. This ensures that each electrode within the flow battery electrode frame assembly can fully contact the electrolyte, improving the performance and efficiency of the flow battery, and making the operation of the flow battery more stable and reliable.

[0023] Optionally, the mother frame includes a matrix and a plurality of microcapsules uniformly dispersed in the matrix. A catalyst is uniformly distributed in the matrix, and a liquid repair agent is stored in the microcapsules. When cracks occur in the matrix, the microcapsules rupture and release the repair agent. The repair agent reacts with the catalyst to achieve self-healing of the cracks.

[0024] By adopting the above technical solution, multiple microcapsules are uniformly dispersed in the matrix of the mother frame, and the catalyst is uniformly distributed within the matrix. Liquid repair agents are stored within the microcapsules. When cracks appear in the matrix, the microcapsules rupture, releasing the repair agents. Because the catalyst is uniformly distributed within the matrix, the released repair agents can quickly contact and react with the catalyst, thereby achieving self-healing of the cracks. This effectively extends the service life of the mother frame, reduces damage to the electrode frame assembly caused by cracks, improves the reliability and stability of the flow battery electrode frame assembly, and reduces maintenance costs and replacement frequency.

[0025] Optionally, the repair agent is dicyclopentadiene, and the catalyst is a Grubb catalyst.

[0026] Optionally, the depth of the main flow channel accounts for 55%-75% of the thickness of the mother frame, the depth of the secondary flow channel accounts for 25%-55% of the thickness of the mother frame, the main flow channel is of the same length, width and depth as the first blind end flow channel, and the secondary flow channel is of the same length, width and depth as the second blind end flow channel.

[0027] By adopting the above technical solution, the proportion of the main flow channel depth to the frame thickness is set to 55%-75%, and the proportion of the secondary flow channel depth to the frame thickness is set to 25%-55%. Furthermore, the main flow channel and the first blind-end flow channel are of equal length, width, and depth, and the secondary flow channel and the second blind-end flow channel are of equal length, width, and depth. When two adjacent frames are face-to-face, the main flow channel and the second blind-end flow channel overlap and connect, and the secondary flow channel and the first blind-end flow channel overlap and connect, thus effectively expanding the flow channel depth. The overall flow channel depth can reach a certain level compared to the overall plate and frame thickness, solving the problem of insufficient flow channel depth caused by plate and frame thickness limitations. Simultaneously, the increased flow channel depth effectively reduces the wall effect, thereby reducing flow resistance and allowing the electrolyte to flow more smoothly within the channel, thus improving the uniformity of flow distribution and contributing to improved performance and efficiency of the flow battery.

[0028] Secondly, the flow battery unit provided in this application adopts the following technical solution:

[0029] A flow battery cell includes:

[0030] At least one pair of flow battery electrode frame assemblies as described in any one of the above contents, and the two sets of flow battery electrode frame assemblies are stacked face to face;

[0031] A proton exchange membrane is disposed between the two parent frames;

[0032] A carbon felt is disposed between the mother frame and the proton exchange membrane.

[0033] By adopting the above technical solution, at least one pair of flow battery electrode frame assemblies are stacked face-to-face. Since the internal flow channels on the mother frame of the flow battery electrode frame assembly overlap and connect in the thickness direction when adjacent mother frames are pressed together, and the common flow channel also connects, the flow channel depth can be greatly widened, solving the problem of insufficient flow channel depth caused by the thickness limitation of the plate frame. Simultaneously, a proton exchange membrane is placed between the two mother frames, and carbon felt is placed between the mother frame and the proton exchange membrane, ensuring the normal operation of the flow battery unit and realizing the function of separating and circulating the positive and negative electrolytes, meeting the usage requirements of flow batteries.

[0034] In summary, this application includes at least one of the following beneficial technical effects:

[0035] 1. When adjacent mother frames are face to face, the internal flow channel group and the common flow channel are connected, thereby widening the flow channel depth within the limited electrode frame thickness, solving the problem of insufficient flow channel depth caused by the plate frame thickness limitation, effectively reducing the wall effect, reducing flow resistance, and improving the uniformity of flow distribution.

[0036] 2. By designing the main flow path, the first blind end flow path, the secondary flow path, and the second blind end flow path in an S-shape or L-shape, the bypass current of the fuel cell stack is reduced, which indirectly improves the energy effect of the fuel cell stack.

[0037] 3. Multiple microcapsules are uniformly dispersed in the matrix of the mother frame, and the catalyst is uniformly distributed in the matrix. Liquid repair agent is stored in the microcapsules. When cracks occur in the matrix, the cracks will cause the microcapsules to rupture, thereby releasing the repair agent. The repair agent can quickly come into contact with the catalyst and react, thereby achieving self-healing of the cracks. This effectively extends the service life of the mother frame, reduces damage to the electrode frame assembly caused by cracks, improves the reliability and stability of the flow battery electrode frame assembly, and reduces maintenance costs and replacement frequency. Attached Figure Description

[0038] Figure 1 This is an exploded structural diagram of a flow battery electrode frame assembly according to Embodiment 1 of this application.

[0039] Figure 2 This is a structural schematic diagram of the front of the mother frame in Embodiment 1 of this application.

[0040] Figure 3 This is a schematic diagram of the sub-frame structure in Embodiment 1 of this application.

[0041] Figure 4 This is a schematic diagram of the structure on the back of the mother frame in Embodiment 1 of this application.

[0042] Figure 5 This is a schematic diagram of the structure of the mother frame in Embodiment 2 of this application.

[0043] Figure 6 This is an exploded structural diagram of a flow battery unit in an embodiment of this application.

[0044] Explanation of reference numerals in the attached figures:

[0045] 1. Mother frame; 11. Common flow channel; 111. Positive electrode inlet; 112. Negative electrode inlet; 113. Positive electrode outlet; 114. Negative electrode outlet; 12. Internal flow channel group; 121. Main flow channel; 122. First blind end flow channel; 123. Secondary flow channel; 124. Second blind end flow channel; 13. Electrode cavity; 14. Guide groove; 141. Flow splitting boss; 15. Electrolyte distribution area; 151. Boss; 16. Perforation; 17. Substrate; 18. Microcapsule; 2. Sub-frame; 21. Assembly boss; 22. Sub-frame hole; 3. Bipolar plate; 4. Proton exchange membrane; 5. Carbon felt. Detailed Implementation

[0046] The following is in conjunction with the appendix Figure 1-6 This application will be described in further detail.

[0047] This application discloses a flow battery electrode frame assembly.

[0048] It should be noted that, in the description of this invention, the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0049] Example 1: Refer to Figure 1 and Figure 2 A flow battery electrode frame assembly includes a mother frame 1, a sub-frame 2 corresponding to the mother frame 1, and a bipolar plate 3 disposed between the sub-frame 2 and the mother frame 1. The mother frame 1 has a common flow channel 11, and internal flow channel groups 12 and electrode cavities 13 are respectively formed on the mother frame 1. When two adjacent mother frames 1 are placed face to face, the internal flow channel groups 12 on the two mother frames 1 overlap and connect in the thickness direction of the mother frame 1, and the common flow channel 11 on the two mother frames 1 connects, thereby expanding the flow channel depth, solving the problem of insufficient flow channel depth caused by the thickness limitation of the plate and frame, reducing flow resistance, and improving the uniformity of flow distribution.

[0050] The common flow channel 11 includes a positive electrode inlet 111, a negative electrode inlet 112, a positive electrode outlet 113, and a negative electrode outlet 114, which are respectively disposed on the mother frame 1. The shape of the common flow channel 11 can be selected in various ways, such as circular, rectangular, elliptical, etc. In this embodiment, the shape of the common flow channel 11 is circular.

[0051] Two sets of internal flow channel groups 12 are provided, and the two sets of internal flow channel groups 12 are symmetrically arranged along the electrode cavity 13. The internal flow channel group 12 includes a main flow channel 121, a first blind end flow channel 122, a secondary flow channel 123, and a second blind end flow channel 124. One main flow channel 121 and one first blind end flow channel 122 are respectively connected to the positive electrode inlet 111, and the other main flow channel 121 and the other first blind end flow channel 122 are respectively connected to the negative electrode outlet 114. The secondary flow channel 123 and the second blind end flow channel 124 are respectively connected to the negative electrode inlet 112, and the other secondary flow channel 123 and the other second blind end flow channel 124 are respectively connected to the positive electrode outlet 113.

[0052] In this embodiment, the main flow channel 121, the first blind flow channel 122, the secondary flow channel 123, and the second blind flow channel 124 are all designed in an S-shape, so that the main flow channel 121 and the first blind flow channel 122 form a double S-shaped flow channel, and the secondary flow channel 123 and the second blind flow channel 124 form a double S-shaped flow channel, thereby better dispersing the flow pressure of the electrolyte.

[0053] In other embodiments, the main flow channel 121, the first blind end flow channel 122, the secondary flow channel 123 and the second blind end flow channel 124 can also be configured as L-shaped. L-shaped flow channels are relatively simple and easy to process and manufacture.

[0054] The depth of the main flow channel 121 is 55%-75% of the thickness of the mother frame 1, and the depth of the secondary flow channel 123 is 25%-55% of the thickness of the mother frame 1. The main flow channel 121 is the same length, width and depth as the first blind end flow channel 122, and the secondary flow channel 123 is the same length, width and depth as the second blind end flow channel 124. This effectively increases the flow channel depth and ensures the uniform flow of electrolyte in the flow channel.

[0055] When two adjacent mother frames 1 are placed face to face, the main flow channel 121 on one mother frame 1 overlaps and connects with the second blind end flow channel 124 on the other mother frame 1, and the secondary flow channel 123 on one mother frame 1 overlaps and connects with the first blind end flow channel 122 on the other mother frame 1. This achieves the purpose of effectively increasing the flow channel depth without increasing the overall thickness of the electrode frame, greatly widening the flow channel depth, reducing the wall effect, reducing flow resistance, and improving the uniformity of flow distribution.

[0056] When two adjacent mother frames 1 are placed face to face, the positive inlet 111 on one mother frame 1 is connected to the negative inlet 112 on the other mother frame 1, and the positive outlet 113 on one mother frame 1 is connected to the negative outlet 114 on the other mother frame 1.

[0057] Reference Figure 2 Two guide channels 14 connected to the electrode cavity 13 are respectively opened on the mother frame 1. The main flow channel 121 connected to the positive electrode inlet 111 is connected to one guide channel 14, and the second blind end flow channel 124 connected to the positive electrode outlet 113 is connected to the other guide channel 14. The two guide channels 14 are arranged in an anti-symmetrical manner.

[0058] A flow-dividing protrusion 141 is provided within the flow channel 14, and electrolyte distribution areas 15 are respectively provided at both ends of the electrode cavity 13, with the electrolyte distribution areas 15 communicating with the flow channel 14. In this embodiment, the flow-dividing protrusion 141 has a T-shaped structure, allowing the electrolyte to be divided into two and flow into the electrolyte distribution area 15. In other embodiments, the flow-dividing protrusion 141 may also be configured to divide the electrolyte into three or four parts.

[0059] The electrolyte distribution area 15 is provided with a number of protrusions 151. The protrusions 151 are evenly distributed in the electrolyte distribution area 15. By cooperating with each other, the flow rate and direction of the electrolyte can be further adjusted, so that the electrolyte can enter the electrode cavity 13 evenly and improve the uniformity of the electrochemical reaction.

[0060] Reference Figure 1 The mother frame 1 is provided with an electrode assembly area for assembling the bipolar plate 3. The sub-frame 2 is detachably connected to the mother frame 1, and the sub-frame 2 is integrally formed with an assembly boss 21. The mother frame 1 has an assembly groove on the side away from the electrode cavity 13. The assembly boss 21 matches the assembly groove to achieve accurate installation of the sub-frame 2 and the mother frame 1, thereby facilitating the confinement of the bipolar plate 3 between the sub-frame 2 and the mother frame 1.

[0061] In this embodiment, the sub-frame 2 is typically made of a material that matches the mother frame 1, and its shape and size are adapted to the mother frame 1. The bipolar plate 3 serves to conduct electricity and separate the positive and negative electrolytes, and is typically made of a material with good conductivity and corrosion resistance, such as graphite plate.

[0062] Reference Figure 1 and Figure 3 The sub-frame 2 is also provided with a flow guide 14, an electrode cavity 13 and an electrolyte distribution area 15 respectively, and the electrode cavity 13 on the sub-frame 2 is provided in correspondence with the electrode cavity 13 on the mother frame 1, and the electrolyte distribution area 15 on the sub-frame 2 is provided in correspondence with the electrolyte distribution area 15 on the mother frame 1.

[0063] Reference Figure 1 and Figure 4 Two perforations 16 are provided on the mother frame 1. One perforation 16 is connected to the first blind end flow channel 122 near the negative electrode outlet 114, and the other perforation 16 is connected to the secondary flow channel 123 near the negative electrode inlet 112.

[0064] Reference Figure 2 and Figure 3 The sub-frame 2 has two sub-frame holes 22, which are set through the flow guide groove 14. When the sub-frame 2 is installed and fixed to the mother frame 1, the sub-frame holes 22 are connected to the through holes 16, so that the electrolyte can flow smoothly between the mother frame 1 and the sub-frame 2, providing electrolyte to the electrode cavity 13 and ensuring the normal operation of the battery.

[0065] The principle of this embodiment is as follows: through the combined structure of the mother frame 1, the sub-frame 2, and the bipolar plate 3, and the special design of the internal flow channel group 12, the flow channel depth is widened when two adjacent mother frames 1 are face to face. The common flow channel 11 ensures the inflow and outflow of electrolyte, and the interconnection of the internal flow channel group 12 allows the electrolyte to be more evenly distributed to each electrode cavity 13, reducing flow resistance and improving the uniformity of flow distribution.

[0066] Example 2: Refer to Figure 5 The difference between this embodiment and Embodiment 1 is that the mother frame 1 includes a substrate 17 and a plurality of microcapsules 18 uniformly dispersed in the substrate 17, and the catalyst is uniformly distributed in the substrate 17.

[0067] The substrate 17 is made of a composite material with self-healing function. In this embodiment, the substrate 17 is made of epoxy resin. The common flow channel 11, the internal flow channel group 12, the electrode cavity 13, the guide groove 14, the electrolyte distribution area 15, and the perforation 16 are respectively arranged on the substrate 17.

[0068] The microcapsule 18 stores a liquid repair agent. The size and distribution of the microcapsule 18 can be adjusted according to actual needs to ensure that the repair agent can be released in time when cracks appear in the substrate 17. In this embodiment, the repair agent is dicyclopentadiene, and the catalyst is a Grubb catalyst.

[0069] When microcracks develop in the mother frame 1 during use due to cyclic pressure, assembly stress, or accidental impact, the propagation of the cracks punctures the microcapsules 18 along their path. Upon rupture, the liquid repair agent stored inside the microcapsules is released and rapidly fills the cracks through capillary action. The repair agent filling the cracks comes into contact with the catalyst pre-distributed in the matrix 17, triggering a rapid polymerization reaction to generate a solid polymer, thereby "bonding" the cracks together and achieving self-healing of the damaged area.

[0070] This application also discloses a flow battery cell.

[0071] Reference Figure 2 and Figure 6 A flow battery unit includes at least one pair of flow battery electrode frame assemblies as described in the above embodiments, and the two sets of flow battery electrode frame assemblies are stacked face to face; a proton exchange membrane 4 is disposed between two mother frames 1; and a carbon felt 5 is disposed between the mother frame 1 and the proton exchange membrane 4.

[0072] In this embodiment, the flow battery unit is the smallest functional repeating unit constituting the flow battery stack, including two identical flow battery electrode frame assemblies, four carbon felts 5 and two proton exchange membranes 4.

[0073] The proton exchange membrane 4 separates the positive and negative electrolytes while allowing protons to pass through. It is made of materials with good proton conductivity and chemical stability, such as perfluorosulfonic acid membranes. The carbon felt 5 has a large specific surface area, providing more reactive sites and improving the battery's reaction efficiency.

[0074] When assembling the flow battery unit, first place the carbon felt 5 in the electrode cavity 13 of the mother frame 1, then place the proton exchange membrane 4 between the two mother frames 1, and then stack the two flow battery electrode frame assemblies face to face so that the internal flow channel group 12 and the common flow channel 11 are accurately connected.

[0075] Once the flow battery unit is assembled, its structure is as follows: mother frame 1, carbon felt 5, proton exchange membrane 4, carbon felt 5, mother frame 1, sub-frame 2, carbon felt 5, proton exchange membrane 4, carbon felt 5, sub-frame 2. One single cell is formed between two mother frames 1, and the other single cell is formed between two sub-frames 2.

[0076] The implementation principle of a flow battery cell in this application embodiment is as follows: when two mother frames 1 are stacked face to face, the main flow channel 121 on one mother frame 1 coincides with the second blind end flow channel 124 on the other mother frame 1, and the secondary flow channel 123 on one mother frame 1 coincides with the first blind end flow channel 122 on the other mother frame 1, so as to form a combined flow channel.

[0077] When the positive electrode electrolyte enters through the positive electrode inlet 111, a portion of the positive electrode electrolyte flows into the main flow channel 121 of the mother frame 1, while the other portion flows into the first blind-end flow channel 122 of the mother frame 1. The electrolyte entering the main flow channel 121 flows through the main flow channel 121 and the second blind-end flow channel 124 on the other mother frame 1 into a guide channel 14, and then sequentially flows through the electrolyte distribution area 15, electrode cavity 13, electrolyte distribution area 15, another guide channel 14, and the second blind-end flow channel 124 on the same side, finally flowing out from the positive electrode outlet 113, thereby ensuring that the positive electrode electrolyte is evenly supplied to the positive electrode carbon felt 5 located between the two mother frames 1. During this process, the positive electrode electrolyte always flows on the same side of the proton exchange membrane 4.

[0078] When the negative electrode electrolyte enters through the negative electrode inlet 112, a portion of the negative electrode electrolyte flows into the secondary flow channel 123 of the mother frame 1, while the other portion flows into the second blind-end flow channel 124 of the mother frame 1. The electrolyte entering the second blind-end flow channel 124 flows into the guide groove 14 through the second blind-end flow channel 124 and the main flow channel 121 on the other mother frame 1, and then flows sequentially through the electrolyte distribution area 15, electrode cavity 13, electrolyte distribution area 15, guide groove 14, and second blind-end flow channel 124 on the other mother frame 1, finally flowing out from the negative electrode outlet 114, thereby ensuring that the negative electrode electrolyte is evenly supplied to the negative electrode carbon felt 5 located between the two mother frames 1. During this process, after the negative electrode electrolyte flows from the second blind-end flow channel 124 into the main flow channel 121, the negative electrode electrolyte flows on the side of the proton exchange membrane 4 away from the positive electrode electrolyte.

[0079] Electrolyte flowing from the positive electrode inlet 111 into the first blind-end channel 122 flows through the secondary channel 123 on another mother frame 1 into the perforation 16, and then sequentially through the perforation 16 and the sub-frame hole 22 into the guide channel 14 on the sub-frame 2. From there, it flows through the guide channel 14 into the electrolyte distribution area 15 and the electrode cavity 13 on the sub-frame 2. Next, the electrolyte entering the electrode cavity 13 flows through the guide channel 14, the sub-frame hole 22, and the perforation 16 into the first blind-end channel 122 near the positive electrode outlet 113, and then into the secondary channel 123, finally flowing out from the positive electrode outlet 113, thus supplying electrolyte to the single cells on the sub-frame 2 side.

[0080] It should be noted that, to ensure a reliable seal is formed after the two mother frames 1 are face-to-face bonded, preventing electrolyte leakage, in this embodiment, sealing grooves are provided at key locations around the electrode cavity 13, the common flow channel 11, and the outer periphery of the bonding surface of the mother frames 1. A sealing ring made of a corrosion-resistant elastomer material (such as EPDM or fluororubber) is embedded within the sealing groove. When multiple electrode frame assemblies are stacked and pressed together by external clamping force, the sealing ring deforms under pressure, thereby forming a highly efficient static sealing barrier between the bonding interfaces of the two mother frames 1. This structure effectively prevents internal leakage caused by cross-contamination between the positive and negative electrolytes, and also prevents electrolyte leakage to the external environment, thus ensuring the functional integrity and operational safety of the electrode frame assembly.

[0081] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A flow battery electrode frame assembly, characterized in that, include: A mother frame (1) is provided with a common flow channel (11). An internal flow channel group (12) and an electrode cavity (13) are provided on the mother frame (1). The internal flow channel group (12) is connected to the common flow channel (11) and the electrode cavity (13) respectively. When two adjacent mother frames (1) are in face-to-face contact, the internal flow channel groups (12) on the two mother frames (1) overlap and connect in the thickness direction of the mother frame (1), and the common flow channel (11) on the two mother frames (1) is connected. The common flow channel (11) includes a positive electrode inlet (111), a negative electrode inlet (112), a positive electrode outlet (113), and a negative electrode outlet (114) respectively disposed on the mother frame (1). The internal flow channel group (12) is provided in two sets. The two sets of internal flow channel groups (12) are symmetrically arranged along the electrode cavity (13). The positive electrode inlet (111) and the negative electrode inlet (112) are respectively connected to one set of internal flow channel groups (12), and the positive electrode outlet (113) and the negative electrode outlet (114) are respectively connected to the other set of internal flow channel groups (12). The internal flow channel group (12) includes a main flow channel (121), a first blind-end flow channel (122), a secondary flow channel (123), and a second blind-end flow channel (124). One of the main flow channels (121) and one of the first blind-end flow channels (122) are respectively connected to the positive electrode inlet (111), and another of the main flow channels (121) and another of the first blind-end flow channels (122) are respectively connected to the negative electrode outlet (114). One of the secondary flow channels (123) and one of the second blind-end flow channels (124) are respectively connected to the negative electrode outlet. The liquid inlet (112) is connected, and another secondary flow channel (123) and another second blind end flow channel (124) are respectively connected to the positive electrode liquid outlet (113). Two guide grooves (14) connected to the electrode cavity (13) are respectively opened on the mother frame (1). The main flow channel (121) connected to the positive electrode liquid inlet (111) is connected to one of the guide grooves (14). The second blind end flow channel (124) connected to the positive electrode liquid outlet (113) is connected to the other guide groove (14). When two adjacent mother frames (1) are face to face, the main flow channel (121) on one mother frame (1) overlaps and connects with the second blind flow channel (124) on the other mother frame (1), and the secondary flow channel (123) on one mother frame (1) overlaps and connects with the first blind flow channel (122) on the other mother frame (1); Subframe (2) is set on the parent frame (1); A bipolar plate (3) is disposed between the sub-frame (2) and the mother frame (1).

2. The flow battery electrode frame assembly according to claim 1, characterized in that: The main flow channel (121), the first blind flow channel (122), the secondary flow channel (123) and the second blind flow channel (124) are all designed in an S-shape or an L-shape.

3. The flow battery electrode frame assembly according to claim 1, characterized in that: The flow channel (14) is provided with a flow-dividing boss (141), and the two ends of the electrode cavity (13) are respectively provided with electrolyte distribution areas (15). The electrolyte distribution area (15) is connected to the flow channel (14). The electrolyte distribution area (15) is provided with a number of bosses (151). The flow-dividing boss (141) and the number of bosses (151) cooperate to ensure the uniformity of electrolyte entering the electrode cavity (13).

4. The flow battery electrode frame assembly according to claim 1, characterized in that: The mother frame (1) has two perforations (16). One perforation (16) is connected to the first blind end flow channel (122) near the negative electrode outlet (114), and the other perforation (16) is connected to the secondary flow channel (123) near the negative electrode inlet (112). The sub-frame (2) also has the electrode cavity (13) and the guide groove (14). The sub-frame (2) has two sub-frame holes (22). The sub-frame holes (22) pass through the guide groove (14) and are connected to the perforations (16). The electrode cavity (13) on the sub-frame (2) is correspondingly arranged with the electrode cavity (13) on the mother frame (1).

5. The flow battery electrode frame assembly according to claim 1, characterized in that: The mother frame (1) includes a matrix (17) and a plurality of microcapsules (18) uniformly dispersed in the matrix (17). The matrix (17) contains a catalyst, and the microcapsules (18) contain a liquid repair agent. When the matrix (17) develops cracks, the microcapsules (18) rupture and release the repair agent. The repair agent reacts with the catalyst to achieve self-healing of the cracks.

6. The flow battery electrode frame assembly according to claim 5, characterized in that: The repair agent is dicyclopentadiene, and the catalyst is a Grubb catalyst.

7. The flow battery electrode frame assembly according to claim 1, characterized in that: The depth of the main flow channel (121) is 55%-75% of the thickness of the mother frame (1), and the depth of the secondary flow channel (123) is 25%-55% of the thickness of the mother frame (1). The main flow channel (121) is the same length, width and depth as the first blind flow channel (122), and the secondary flow channel (123) is the same length, width and depth as the second blind flow channel (124).

8. A flow battery cell, characterized in that, include: At least one pair of flow battery electrode frame assemblies as described in any one of claims 1-7, and the two sets of flow battery electrode frame assemblies are stacked face to face; A proton exchange membrane (4) is disposed between the two parent frames (1); Carbon felt (5) is disposed between the mother frame (1) and the proton exchange membrane (4).

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