Flow battery monomer, flow battery device and electric equipment

Abstract

The utility model relates to a flow battery monomer, a flow battery device and electric equipment. The flow battery monomer comprises a first electrode frame, a second electrode frame, a diaphragm and a sealing line, the first electrode frame is provided with a first cavity, the second electrode frame and the first electrode frame are arranged in a stacked manner, and the second electrode frame is provided with a second cavity. And the diaphragm is clamped between the first electrode frame and the second electrode frame and is used for isolating the first chamber from the second chamber. Sealing lines are clamped between the first electrode frame and the diaphragm and / or between the second electrode frame and the diaphragm, and the sealing lines are arranged in the first cavity and the second cavity in a surrounding manner; and the sealing lines and the corresponding first electrode frames or second electrode frames form an integrated structure. The sealing lines and the corresponding first electrode frames or second electrode frames form the integrated structure, so that the sealing lines and the first electrode frames or the second electrode frames do not need to be assembled in the assembly process of the flow battery monomer, the assembly steps are saved, and the assembly efficiency of the flow battery monomer is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a flow battery monomer, a flow battery device and an electric device. BACKGROUND

[0002] The flow battery, also known as a redox flow battery, has the advantages of relative stability, flexible design, high efficiency, environmental protection and large-scale energy storage. The flow battery is composed of a plurality of flow battery monomers stacked in sequence. The flow battery monomer includes structures such as an electrode frame, a bipolar plate and a diaphragm. The electrode frame and the bipolar plate, and the electrode plate and the diaphragm enclose a cavity for accommodating electrolyte. The cavity has a sealing requirement to prevent electrolyte from leaking outside the battery.

[0003] In a conventional flow battery device, a sealing wire is clamped between the electrode frame and the diaphragm to achieve a sealed connection between the electrode frame and the diaphragm. The sealing wire encloses the cavity to prevent electrolyte from leaking. However, when the sealing wire is assembled with the electrode frame, there are problems of time-consuming and laborious assembly and poor assembly consistency. CONTENT OF THE UTILITY MODEL

[0004] Therefore, it is necessary to provide a flow battery monomer, a flow battery device and an electric device to solve the problem of difficult assembly of the sealing wire and the electrode frame.

[0005] In a first aspect, the present application provides a flow battery monomer, which comprises:

[0006] a first electrode frame, the first electrode frame being provided with a first cavity;

[0007] a second electrode frame, the second electrode frame being stacked with the first electrode frame, the second electrode frame being provided with a second cavity;

[0008] a diaphragm, the diaphragm being clamped between the first electrode frame and the second electrode frame to isolate the first cavity and the second cavity;

[0009] a sealing wire, the sealing wire being clamped between the first electrode frame and the diaphragm, and / or between the second electrode frame and the diaphragm, the sealing wire enclosing the first cavity and the second cavity;

[0010] The sealing wire and the corresponding first electrode frame or second electrode frame are configured as an integrated structure.

[0011] In one embodiment, the first electrode frame and / or the second electrode frame are provided with a mounting groove on the side facing each other. The first end of the sealing wire is integrally connected in the mounting groove, and the second end of the sealing wire extends outwardly from the mounting groove.

[0012] In one of the embodiments, the second end protrudes from the side of the connected first electrode frame or second electrode frame and elastically abuts against the diaphragm.

[0013] In one of the embodiments, the first end is provided with at least one clamping groove, and a clamping protrusion is correspondingly arranged on the groove bottom or groove wall of the mounting groove.

[0014] In one of the embodiments, the side of the first electrode frame and / or the second electrode frame facing each other is further provided with an avoiding groove, the avoiding groove is in communication with the mounting groove, and the second end is located in the avoiding groove.

[0015] In one of the embodiments, the sealing line is arranged in a ring shape, and in the direction perpendicular to the circumferential direction of the sealing line, the size of the avoiding groove is greater than the size of the second end.

[0016] In one of the embodiments, the sealing line is arranged in a ring shape, and in the direction perpendicular to the circumferential direction of the sealing line, the second end includes a plurality of spaced apart abutting protrusions, and the abutting protrusions abut against the diaphragm.

[0017] In one of the embodiments, the flow battery cell further comprises:

[0018] A bipolar plate is arranged on the side of the first electrode frame or the second electrode frame away from the diaphragm, and the side of the first electrode frame or the second electrode frame facing the bipolar plate is provided with a glue storage groove, and the glue storage groove is provided with sealing glue to be bonded with the bipolar plate through the sealing glue.

[0019] In one of the embodiments, the first chamber and the second chamber respectively include a liquid storage cavity and a flow channel groove in communication, and the flow channel groove is arranged on the side of the first electrode frame and the second electrode frame away from each other.

[0020] The flow battery cell further comprises a cover plate, and the cover plate covers the flow channel groove to form a flow channel cavity together with the corresponding first electrode frame or second electrode frame.

[0021] In one of the embodiments, the first electrode frame or the second electrode frame is provided with a fusion groove around the flow channel groove, and the cover plate is fused in the fusion groove.

[0022] In a second aspect, the application provides a flow battery device, which comprises a plurality of flow battery cells as described in any of the embodiments above, and the plurality of flow battery cells are sequentially stacked.

[0023] In a third aspect, the application provides a power consumption device, which comprises a flow battery device as described in any of the embodiments above, and the flow battery device is used to provide electric energy.

[0024] The flow battery cell has a sealing wire clamped between the first electrode frame and the diaphragm and / or between the second electrode frame and the diaphragm, and the sealing wire surrounds the first chamber and the second chamber, so as to realize the sealed connection between the first electrode frame and the diaphragm and between the second electrode frame and the diaphragm through the sealing wire, and prevent the electrolyte in the first chamber and the second chamber from leaking. Since the sealing wire and the corresponding first electrode frame or second electrode frame are configured in an integrated structure, the sealing wire and the first electrode frame or the second electrode frame do not need to be assembled during the assembly of the flow battery cell, the assembly steps are saved, and the assembly efficiency of the flow battery cell is improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 An exploded structural schematic view of the flow battery cell provided in an embodiment of the present application is shown;

[0026] Figure 2 A planar structural schematic view of the flow battery cell provided in an embodiment of the present application is shown;

[0027] Figure 3 A sectional view of A-A in FIG. 1 is shown; Figure 2 A sectional view of B in FIG. 1 is shown;

[0028] Figure 4 An enlarged structural view of B in FIG. 1 is shown; Figure 3 An exploded structural schematic view of the first electrode frame and the sealing wire provided in an embodiment of the present application is shown.

[0029] Figure 5 An exploded structural schematic view of the first electrode frame and the sealing wire provided in an embodiment of the present application is shown.

[0030] BRIEF DESCRIPTION OF DRAWINGS

[0031] 1. first electrode frame; 11. first chamber; 111. liquid storage cavity; 112. flow channel groove; 12. mounting groove; 121. clamping protrusion; 13. avoiding groove; 14. fusion groove;

[0032] 2. second electrode frame; 21. second chamber;

[0033] 3. diaphragm;

[0034] 4. sealing wire; 41. first end; 411. clamping groove; 42. second end; 421. abutting protrusion;

[0035] 5. bipolar plate;

[0036] 6. cover plate;

[0037] 7. sealing glue. DETAILED DESCRIPTION

[0038] In order to make the above objectives, features and advantages of the present application more clear and comprehensible, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of different ways beyond the specific embodiments described herein and by one of ordinary skill in the art without departing from the spirit and scope of the present application, and it is therefore intended that all such variations be considered as falling within the scope of the present application. It should be understood that the use of the terms "include", "comprise" or "contain" herein should not be understood as limiting the present application to the features or steps described herein, but rather the use of these terms is intended to cover the presence of the features or steps described herein as well as the presence of other features or steps not described herein.

[0039] In the description of the present application, it should be understood that, if these terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0040] In addition, if these terms "first", "second" appear, these terms are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features referred to. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, if the term "a plurality of" appears, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0041] In the present application, unless otherwise specifically defined and limited, if the terms "mount", "connect", "connect", "fix" and the like appear, these terms should be broadly understood. For example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0042] In the present application, unless specifically defined and limited otherwise, if there is a description of a first feature on or above or below a second feature, it can mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature can be above or above or above the second feature, or it can only mean that the first feature is higher than the second feature in horizontal height. The first feature can be below or below or below the second feature, or it can only mean that the first feature is lower than the second feature in horizontal height.

[0043] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or there can be an intermediate element. If an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be an intermediate element. If present, the terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used in the present application are only for illustrative purposes and do not represent the only implementation.

[0044] Referring to Figure 1 , Figure 1 A decomposition structure diagram of a flow battery cell provided in an embodiment of the present application is shown. The embodiment of the present application provides a flow battery cell, which includes a first electrode frame 1, a second electrode frame 2 and a diaphragm 3. The first electrode frame 1 is provided with a first chamber 11, and the second electrode frame 2 is stacked with the first electrode frame 1. The second electrode frame 2 is provided with a second chamber 21. The diaphragm 3 is clamped between the first electrode frame 1 and the second electrode frame 2, and is used to isolate the first chamber 11 and the second chamber 21. The first electrode frame 1 and the second electrode frame 2 are positive electrode frame and negative electrode frame respectively, and the first chamber 11 and the second chamber 21 contain positive electrolyte and negative electrolyte respectively. The diaphragm 3 is clamped between the first electrode frame 1 and the second electrode frame 2, and the positive electrolyte and the negative electrolyte realize ion exchange through the diaphragm 3. This is the conventional structure of the flow battery cell in the prior art, and the specific structure and working principle thereof will not be described here.

[0045] Further, the flow battery cell further comprises a bipolar plate 5 arranged on the side of the first electrode frame 1 or the second electrode frame 2 away from the diaphragm 3, and the bipolar plate 5, the first electrode frame 1 and the diaphragm 3 enclose the first chamber 11, or the bipolar plate 5, the second electrode frame 2 and the diaphragm 3 enclose the second chamber 21. Generally, one bipolar plate 5 is included in one flow battery cell, and when a plurality of flow battery cells are stacked, the bipolar plate 5 is arranged on the side of the first electrode frame 1, and the bipolar plate 5 is in contact with the second electrode frame 2 of the adjacent flow battery cell, and can enclose the second chamber 21 with the second electrode frame 2 of the adjacent flow battery cell.

[0046] In some embodiments, referring to Figure 1 , the flow battery cell further comprises a sealing line 4 arranged between the first electrode frame 1 and the diaphragm 3, and / or between the second electrode frame 2 and the diaphragm 3, and the sealing line 4 encloses the first chamber 11 and the second chamber 21. The sealing line 4 and the corresponding first electrode frame 1 or second electrode frame 2 are configured as an integrated structure.

[0047] The flow battery cell provided by the embodiments of the present application has the sealing line 4 arranged between the first electrode frame 1 and the diaphragm 3, and / or between the second electrode frame 2 and the diaphragm 3, and the sealing line 4 encloses the first chamber 11 and the second chamber 21, so as to realize the sealed connection between the first electrode frame 1 and the diaphragm 3, and between the second electrode frame 2 and the diaphragm 3 through the sealing line 4, and prevent the electrolyte in the first chamber 11 and the second chamber 21 from leaking. Since the sealing line 4 and the corresponding first electrode frame 1 or second electrode frame 2 are configured as an integrated structure, the sealing line 4 and the first electrode frame 1 or the second electrode frame 2 do not need to be assembled during the assembly of the flow battery cell, which saves the assembly steps and is beneficial to improving the assembly efficiency of the flow battery cell.

[0048] In some embodiments, referring to Figures 2-4 , the sealing line 4 is arranged between the first electrode frame 1 and the diaphragm 3, and between the second electrode frame 2 and the diaphragm 3. It can be understood that the sealing line 4 between the first electrode frame 1 and the diaphragm 3 and the sealing line 4 between the second electrode frame 2 and the diaphragm 3 can adopt the same structure or different structures, as long as they can realize the sealing function respectively.

[0049] Optionally, the first electrode frame 1 and the second electrode frame 2 are made of plastic material and can be processed by injection molding. During the injection molding process, the sealing line 4 can be embedded in the injection mold to integrally injection mold the sealing line 4 with the first electrode frame 1 and the sealing line 4 with the second electrode frame 2 to form an integrated structure. The integrated injection molding processing method is beneficial to improving the strength of the connection structure and has high processing efficiency.

[0050] Of course, the integral processing between the sealing line 4 and the first electrode frame 1 and between the sealing line 4 and the second electrode frame 2 can be achieved by 3D printing, hot pressing, vulcanization bonding or other ways besides the injection molding process, as long as the sealing line 4 and the first electrode frame 1 and the second electrode frame 2 can be firmly connected as an integral structure. The specific processing method is not limited here.

[0051] Optionally, the sealing line 4 can be made of EPDM rubber or fluorine-containing rubber or strong acid and alkali resistant material.

[0052] Please refer to Figure 4 and Figure 5 In some embodiments, the side of the first electrode frame 1 and / or the second electrode frame 2 facing each other is provided with a mounting groove 12, the first end 41 of the sealing line 4 is integrally connected in the mounting groove 12, and the second end 42 of the sealing line 4 extends out of the mounting groove 12. By providing the mounting groove 12, the mounting space is provided for the sealing line 4, and the sealing line 4 will not completely protrude from the first electrode frame 1 or the second electrode frame 2, so as to reduce the gap between the first electrode frame 1 and the second electrode frame 2, thereby being able to clamp the diaphragm 3.

[0053] Specifically, the second end 42 protrudes from the side of the connected first electrode frame 1 or second electrode frame 2 and elastically abuts against the diaphragm 3. Under the pressure of the first electrode frame 1 and the second electrode frame 2, the sealing line 4 elastically deforms to tightly abut against the diaphragm 3, thereby achieving good sealing effect.

[0054] In some embodiments, please continue to refer to Figure 4 and Figure 5 The first end 41 is provided with at least one clamping groove 411, and the groove bottom or groove wall of the mounting groove 12 is correspondingly provided with a clamping protrusion 121, and the clamping groove 411 is matched with the clamping protrusion 121. By matching the clamping groove 411 and the clamping protrusion 121, the contact area between the sealing line 4 and the corresponding first electrode frame 1 or second electrode frame 2 is increased, thereby improving the connection strength between the sealing line 4 and the corresponding first electrode frame 1 or second electrode frame 2, which is beneficial to prevent the sealing line 4 from falling off from the first electrode frame 1 or the second electrode frame 2.

[0055] In the embodiments of the present application, the clamping groove 411 is arranged on the end face of the sealing line 4 facing the first electrode frame 1 or the second electrode frame 2, and the clamping protrusion 121 is correspondingly arranged on the groove bottom of the mounting groove 12. It can be understood that the clamping groove 411 can also be arranged on the side wall of the sealing line 4, and correspondingly the clamping protrusion 121 is arranged on the groove wall of the mounting groove 12. In this case, the clamping protrusion 121 blocks and limits the sealing line 4 in the arrangement direction of the first electrode frame 1 and the second electrode frame 2, which is more beneficial to prevent the sealing line 4 from falling off from the first electrode frame 1 or the second electrode frame 2.

[0056] In some embodiments, the side of the first electrode frame 1 and / or the second electrode frame 2 facing each other is further provided with an avoiding groove 13, the avoiding groove 13 is in communication with the mounting groove 12, and the second end 42 is located in the avoiding groove 13. The sealing line 4 is arranged in a ring shape, and in the circumferential direction perpendicular to the sealing line 4, the size of the avoiding groove 13 is greater than the size of the second end 42. By arranging the avoiding groove 13 with a size greater than the second end 42, a deformation space is provided for the sealing line 4, and when the sealing line 4 is deformed by being pressed by the first electrode frame 1 and the second electrode frame 2, the sealing line 4 can be deformed into the avoiding groove 13, so that the first electrode frame 1 and the second electrode frame 2 can be closer to each other to clamp the diaphragm 3.

[0057] In some embodiments, the width W1 of the mounting groove 12 is generally 1mm-3mm, for example, it can be 2.3mm. The width W2 of the first end 41 is arranged to be the same size as the width W1 of the mounting groove 12, and is also arranged to be 1mm-3mm.

[0058] The depth L1 of the mounting groove 12 is generally 2mm-4mm, for example, it can be 3mm. The depth L2 of the avoiding groove 13 is less than the depth of the mounting groove 12, and is generally 1mm-3mm, and a suitable value is selected according to the depth of the mounting groove 12. When the depth L1 of the mounting groove 12 is 3mm, the depth L2 of the avoiding groove 13 is generally 1mm.

[0059] In some embodiments, in the circumferential direction perpendicular to the sealing line 4, the second end 42 includes a plurality of spaced apart abutting protrusions 421, and the abutting protrusions 421 abut the diaphragm 3. By arranging a plurality of spaced apart abutting protrusions 421, a plurality of layers of sealing are formed outwardly from the first chamber 11 and the second chamber 21, thereby further improving the sealing reliability of the sealing line 4.

[0060] In some embodiments, as shown in Figure 1 and Figure 4 The side of the first electrode frame 1 or the second electrode frame 2 facing the bipolar plate 5 is provided with a glue storage groove (not shown in the figure), and the glue storage groove is provided with sealing glue 7, so as to be bonded to the bipolar plate 5 through the sealing glue 7. The sealing glue 7 can be glue, which is coated on the corresponding first electrode frame 1 or second electrode frame 2, and then the bipolar plate 5 is assembled on the first electrode frame 1 or the second electrode frame 2, and the glue is solidified to realize the bonding of the first electrode frame 1 or the second electrode frame 2 and the bipolar plate 5. The arrangement of the glue storage groove is beneficial to the precise arrangement of the sealing glue 7.

[0061] Specifically, a circle of glue storage grooves is arranged on the first electrode frame 1 or the second electrode frame 2 around the first chamber 11 and the second chamber 21, and the glue is solidified to form a ring-shaped sealing glue 7, so as to prevent the electrolyte in the first chamber 11 and the second chamber 21 from leaking.

[0062] In some embodiments, in combination withFigure 3 and Figure 4 As shown in the figure, the first chamber 11 and the second chamber 21 have substantially the same structure, and each includes a liquid storage cavity 111 and a flow channel groove 112 in communication. The flow channel groove 112 is arranged on the side of the first electrode frame 1 and the second electrode frame 2 away from each other. The flow battery cell further includes a cover plate 6, which is arranged on the flow channel groove 112 to form a flow channel cavity with the corresponding first electrode frame 1 or the second electrode frame 2, and the electrolyte is injected into the liquid storage cavity 111 through the flow channel cavity. The first electrode frame 1 or the second electrode frame 2 is provided with a welding groove 14 around the flow channel groove 112, and the cover plate 6 is welded in the welding groove 14. By arranging the welding groove 14, the cover plate 6 is positioned to improve the convenience of installing the cover plate 6.

[0063] Further, the welding groove 14 is provided with a welding bump at the bottom of the groove, and after the cover plate 6 is placed in the welding groove 14, the welding bump is melted at high temperature to connect the cover plate 6 to the bottom of the welding groove 14. Specifically, the welding bump is arranged in a continuous structure around the flow channel groove 112 to seal the connection between the cover plate 6 and the corresponding first electrode frame 1 or the second electrode frame 2.

[0064] The embodiment of the present application also provides a flow battery device, which includes a plurality of flow battery cells as in the above embodiment, and the plurality of flow battery cells are arranged in sequence.

[0065] The embodiment of the present application also provides a power utilization device, which includes a flow battery device as in the above embodiment, and the flow battery device is used to provide electric energy.

[0066] The technical features of the above embodiments can be combined in any way. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present application.

[0067] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. A flow battery cell, characterized in that, The flow battery cell comprises: a first electrode frame provided with a first cavity; a second electrode frame provided in a stack with the first electrode frame, the second electrode frame being provided with a second cavity; a diaphragm arranged between the first electrode frame and the second electrode frame for isolating the first cavity and the second cavity; a sealing line arranged between the first electrode frame and the diaphragm and / or between the second electrode frame and the diaphragm, the sealing line surrounding the first cavity and the second cavity; wherein the sealing line and the corresponding first electrode frame or second electrode frame are configured as an integral structure.

2. The flow battery cell of claim 1, wherein, The first electrode frame and / or the second electrode frame are provided with a mounting groove on the side facing each other, the first end of the sealing line is integrally connected in the mounting groove, and the second end of the sealing line extends out of the mounting groove.

3. The flow battery cell of claim 2, wherein, The second end protrudes from the side of the connected first electrode frame or second electrode frame and elastically abuts against the diaphragm.

4. The flow battery cell of claim 2, wherein, The first end is provided with at least one clamping groove, and a clamping protrusion is correspondingly arranged on the groove bottom or groove wall of the mounting groove, and the clamping groove is matched with the clamping protrusion.

5. The flow battery cell of claim 2, wherein, The first electrode frame and / or the second electrode frame are further provided with an avoiding groove on the side facing each other, the avoiding groove is in communication with the mounting groove, and the second end is located in the avoiding groove; wherein the sealing line is arranged in a ring shape, and in a direction perpendicular to the surrounding direction of the sealing line, the size of the avoiding groove is greater than the size of the second end.

6. The flow battery cell of claim 2, wherein, The sealing line is arranged in a ring shape, and in a direction perpendicular to the surrounding direction of the sealing line, the second end comprises a plurality of spaced apart abutting protrusions, and the abutting protrusions abut against the diaphragm.

7. The flow battery cell of any one of claims 1-6, wherein, The flow battery cell further comprises: a bipolar plate arranged on the side of the first electrode frame or the second electrode frame away from the diaphragm, the side of the first electrode frame or the second electrode frame facing the bipolar plate is provided with a glue storage groove, and the glue storage groove is provided with sealing glue for bonding with the bipolar plate through the sealing glue.

8. The flow battery cell of any one of claims 1-6, wherein, The first cavity and the second cavity respectively comprise a liquid storage cavity and a flow channel groove in communication, and the flow channel groove is arranged on the side of the first electrode frame and the second electrode frame away from each other; The flow battery cell further comprises a cover plate, and the cover plate covers the flow channel groove to form a flow channel cavity with the corresponding first electrode frame or second electrode frame; wherein the first electrode frame or the second electrode frame is provided with a fusion groove around the flow channel groove, and the cover plate is fused in the fusion groove.

9. A flow battery device, characterized by The flow battery cell comprises a plurality of flow battery cells as claimed in any one of claims 1-8, and the plurality of flow battery cells are arranged in a stack.

10. An electric device, characterized by The flow battery device as claimed in claim 9 is used to provide electric energy.

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