Sealing top cover and lithium battery

Abstract

The sealing top cover is used for sealing a liquid injection opening in a cover plate of the lithium battery, the sealing top cover comprises a cover cap, a sealing piece and a plurality of elastic pieces, the cover cap is provided with a containing cavity with an opening in one end, the cover cap covers the liquid injection opening of the cover plate, the end face of the cover cap is connected with the cover plate in a sealed mode, and the elastic pieces are arranged in the containing cavity. An operation opening penetrating through the cap in the thickness direction is formed in the cap, and the operation opening is communicated with the containing cavity and the liquid injection opening; the sealing element is arranged in the accommodating cavity; the plurality of elastic pieces are arranged in the accommodating cavity at intervals, and each elastic piece is pressed between the sealing piece and the cover plate; the sealing piece seals the operation opening under the action of the restoring force of the elastic piece. The end, facing the operation opening, of the sealing piece can operably move in the direction close to the cover plate so as to open the operation opening. Through the structural form, the sealing top cover can be ensured to be capable of continuously supplementing liquid or helium, so that the flow of liquid supplementing and helium detection is simplified, and in addition, the sealing structure has the advantage of being reliable in sealing.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a sealed top cover and a lithium battery. Background Art

[0002] With the vigorous development of the new energy industry, the energy storage industry has also gradually emerged, and energy storage batteries have received widespread attention. In the production and processing of lithium batteries, the electrolyte is poured into the battery from the injection hole, and then the injection hole is sealed. This causes some water to enter the battery during the injection and sealing process, resulting in a decrease in the performance of the battery cell. In addition, during the use of the battery cell, the battery cell itself will consume part of the electrolyte and produce certain gases, which will affect the relevant performance of the battery cell and affect the service life of the battery cell.

[0003] After the electrolyte is injected into the lithium-ion batteries currently in production, sealing pins are used for sealing, and then the sealing pins are welded to the battery cover. During the battery cell cycle, gas is generated and a certain amount of electrolyte is consumed, which will reduce the performance of the battery cell. In the related art, since the sealing pins are welded to the top cover of the battery cell, they cannot be disassembled for exhaust and refilling. Utility Model Content

[0004] Based on this, it is necessary to provide a sealed top cover and a lithium battery to address the technical problem that the sealing structure of the liquid filling port of the cover plate of the lithium battery in the related art cannot achieve exhaust and liquid replenishment.

[0005] A sealing top cover is used to seal a liquid injection port on a cover plate of a lithium battery, and the sealing top cover comprises:

[0006] A cap is configured to have a receiving cavity with an opening at one end, the cap is disposed at the liquid injection port of the cover plate, and the end surface of the cap is sealed and connected to the cover plate, the cap is configured to have an operation port that passes through the cap in the thickness direction, and the operation port is connected to the receiving cavity and the liquid injection port;

[0007] A sealing member, disposed in the accommodating cavity;

[0008] A plurality of elastic members are arranged in the accommodating cavity at intervals, and each of the elastic members is pressed between the sealing member and the cover plate;

[0009] Wherein, the sealing member seals the operation port under the action of the restoring force of the elastic member; the end of the sealing member facing the operation port can be operably moved toward the direction close to the cover plate to open the operation port.

[0010] In one of the embodiments, a plurality of first positioning grooves are provided on the periphery of the liquid injection port on the cover plate, a plurality of second positioning grooves corresponding to the first positioning grooves are provided on the end surface of the seal facing the cover plate, and the two ends of the elastic member are respectively embedded in the first positioning groove and the second positioning groove.

[0011] In one embodiment, a circle formed by a line connecting the centers of the projections of the plurality of second positioning grooves on the end surface of the seal is concentric with the circle where the end surface of the seal is located.

[0012] In one embodiment, the outer radius of the seal is defined as R1, the radius of the second positioning groove is defined as R2, the radius of the projection of the plurality of second positioning grooves on the end surface of the seal is defined as R3, and R1>R2+R3;

[0013] When the number of the elastic members is 3, R3>2R2;

[0014] Alternatively, when the number of the elastic members is 2, .

[0015] In one embodiment, the sealing cover further comprises:

[0016] A sealing ring is disposed between the sealing member and the cover cap, and the sealing ring can be elastically deformed to seal the gap between the sealing member and the cover cap.

[0017] In one embodiment, the sealing ring is bonded and fixed to the cap.

[0018] In one embodiment, the seal is configured as a metal material structure.

[0019] In one embodiment, the side surface of the sealing member facing the cap is configured as an inclined surface, and the diameter of the sealing member gradually increases from the end facing the cap to the end away from the cap.

[0020] A lithium battery comprises the sealing top cover as described above.

[0021] In one of the embodiments, the lithium battery further includes a pole, which is disposed on the cover plate and protrudes from the cover plate, and the distance that the pole protrudes from the cover plate is greater than the distance that the cap protrudes from the cover plate.

[0022] Beneficial effects of the utility model:

[0023] The utility model provides a sealing top cover, which is used to seal the liquid injection port on the cover plate of the lithium battery, so that the liquid injection port is sealed. By setting the cap cover at the liquid injection port, setting the sealing member in the accommodating cavity of the cap, and pressing the elastic member between the sealing member and the cover plate, so that the sealing member seals the operating port under the restoring force of the elastic member, the sealing of the operating port is achieved, thereby achieving the sealing of the liquid injection port of the cover plate. Since an elastic member is arranged between the sealing member and the cap, when the sealing member is acted on by the operating port, the sealing member can move toward the top cover, thereby opening the operating port, so that the battery can be injected with liquid or helium through the operating port, thereby simplifying the process of liquid injection or helium inspection. In addition, by arranging multiple elastic members between the sealing member and the cover plate, even if some of the elastic members fail, it will not affect the sealing function of the sealing top cover, thereby helping to enhance the reliability of the sealing top cover. Through the above structural form, it can not only ensure that the sealing top cover can continuously replenish liquid or helium, thereby simplifying the process of liquid replenishment and helium inspection, but also has the advantage of reliable sealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG1 is a schematic structural diagram of a sealing top cover provided by an embodiment of the present invention after being installed on a cover plate of a lithium battery;

[0025] FIG2 is an enlarged schematic diagram of A in FIG1 ;

[0026] FIG3 is a schematic diagram of an exploded structure of a sealing top cover provided in one embodiment of the utility model;

[0027] FIG4 is a schematic structural diagram of a cover cap in a sealing top cover provided by an embodiment of the utility model;

[0028] FIG5 is a cross-sectional schematic diagram of a cover cap in a sealing top cover provided by an embodiment of the utility model;

[0029] FIG6 is a cross-sectional schematic diagram of a sealing member in a sealing top cover provided in an embodiment of the utility model;

[0030] FIG7 is a schematic structural diagram of a sealing member in a sealing top cover on the second positioning groove side provided by an embodiment of the utility model;

[0031] FIG8 is a schematic structural diagram of a sealing member in a sealing top cover provided by an embodiment of the utility model from another perspective;

[0032] FIG9 is a top view of a sealing member in a sealing top cover provided in an embodiment of the utility model;

[0033] FIG10 is a schematic diagram of the structure of a sealing ring provided in one embodiment of the utility model;

[0034] FIG. 11 is a schematic structural diagram of an elastic member in a sealing top cover provided in an embodiment of the present utility model.

[0035] Reference numerals:

[0036] Sealing top cover 100; cover cap 110; operation port 111; sealing ring positioning groove 112; accommodating cavity 113; sealing member 120; second positioning groove 121; elastic member 130; sealing ring 140; cover plate 200; liquid injection port 210; first positioning groove 220; lower plastic 300; pole 400. DETAILED DESCRIPTION

[0037] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0039] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0040] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0042] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0043] Referring to FIGS. 1 to 11 , an embodiment of the utility model provides a sealing top cover 100 for sealing a liquid injection port 210 on a cover plate 200 of a lithium battery. The sealing top cover 100 comprises a cap 110, a sealing member 120 and a plurality of elastic members 130. The cap 110 is configured with a receiving cavity 113 with an opening at one end. The cap 110 is disposed at the liquid injection port 210 of the cover plate 200, and the end surface of the cap 110 is sealed and connected to the cover plate 200. The cap 110 is configured with an operating member 120 that penetrates the cap 110 in the thickness direction. The operating port 111 is connected with the accommodating cavity 113 and the liquid injection port 210; the sealing member 120 is arranged in the accommodating cavity 113; a plurality of elastic members 130 are arranged at intervals in the accommodating cavity 113, and each elastic member 130 is pressed between the sealing member 120 and the cover plate 200; wherein, the sealing member 120 seals the operating port 111 under the action of the restoring force of the elastic member 130; the end of the sealing member 120 toward the operating port 111 can be operably moved toward the direction close to the cover plate 200 to open the operating port 111.

[0044] The present embodiment provides a sealing top cover 100, which is used to seal the liquid injection port 210 on the cover plate 200 of the lithium battery, so as to seal the liquid injection port 210. By setting the cap 110 at the liquid injection port 210, setting the sealing member 120 in the accommodating cavity 113 of the cap 110, and pressing the elastic member 130 between the sealing member 120 and the cover plate 200, so that the sealing member 120 seals the operating port 111 under the restoring force of the elastic member 130, the sealing of the operating port 111 is achieved, and the sealing of the liquid injection port 210 of the cover plate 200 is achieved. Since the elastic member 130 is provided between the sealing member 120 and the cap 110, when the sealing member 120 is acted on by the operating port 111, the sealing member 120 can move in the direction close to the top cover, thereby opening the operating port 111, so that the battery can be injected with liquid or helium through the operating port 111, thereby simplifying the process of liquid injection or helium inspection. In addition, by arranging a plurality of elastic members 130 between the sealing member 120 and the cover plate 200, even if some of the elastic members 130 fail, it will not affect the sealing function of the sealing top cover 100, thereby facilitating the reliability of the sealing top cover 100. The above structure can not only ensure that the sealing top cover 100 can be continuously replenished with liquid or helium, thereby simplifying the process of replenishing liquid and helium detection, but also has the advantage of reliable sealing.

[0045] In the present embodiment, the cap 110 is fixedly connected to the cover plate 200 by welding, and sealing is also achieved. The elastic member 130 is a spring, and there is no limit on the number of springs, which can be two, three or even more. In the present embodiment, as shown in FIG3 , four springs are arranged in a cap 110. The spring is always in a compressed state, so that in the absence of external force, the spring can push the sealing member 120 toward the operating port 111, thereby sealing the operating port 111 through the sealing member 120. Furthermore, a plurality of elastic members 130 are arranged around the periphery of the liquid injection port 210. By arranging a plurality of elastic members 130, that is, springs around the periphery of the liquid injection port 210, the force applied by each elastic member 130 on the sealing member 120 is more balanced, thereby improving the reliability of sealing the operating port 111.

[0046] As shown in FIG. 1 and FIG. 2 , specifically, the cover plate 200 is a plain aluminum sheet, on which a liquid injection port 210 for liquid injection is provided, and a lower plastic 300 for insulation is provided below the plain aluminum sheet, and a through hole corresponding to the liquid outlet is provided on the lower plastic 300 .

[0047] In one embodiment, as shown in FIG. 2 , a plurality of first positioning grooves 220 are provided on the periphery of the liquid injection port 210 on the cover plate 200. As shown in FIG. 6 and FIG. 7 , a plurality of second positioning grooves 121 corresponding to the first positioning grooves 220 are provided on the end surface of the sealing member 120 facing the cover plate 200. The two ends of the elastic member 130 are respectively embedded in the first positioning groove 220 and the second positioning groove 121. Specifically, in this embodiment, the cross-sectional shape of the first positioning groove 220 and the second positioning groove 121 is circular. Of course, in other embodiments, the cross-sectional shape of the above positioning grooves can be set to a square, an ellipse, etc. The elastic member 130 is embedded in the first positioning groove 220 and the second positioning groove 121. The two ends of the elastic member 130, that is, the spring, are fixed by the first positioning groove 220 and the second positioning groove 121 to ensure that the position of the elastic member 130 remains unchanged, thereby improving the reliability of the elastic member 130 exerting a force on the sealing member 120, and further ensuring the reliability of the sealing member 120 sealing the operation port 111.

[0048] As shown in Fig. 9, further, the circle formed by the line connecting the centers of the projections of the plurality of second positioning grooves 121 on the end surface of the seal 120 is concentric with the circle where the end surface of the seal 120 is located. In this way, the second positioning grooves 121 are evenly distributed on the end surface of the seal 120 facing the cover plate, so that the elastic members 130 can be evenly distributed on the seal 120, and further the forces applied by the plurality of elastic members 130 on the seal 120 are evenly distributed, so that the seal of the seal 120 on the operation port 111 is more reliable.

[0049] Specifically, the outer radius of the seal is defined as R1, the radius of the second positioning groove is defined as R2, and the radius of the projection of the plurality of second positioning grooves on the end surface of the seal is defined as R3, R1>R2+R3; when the number of elastic members is 3, R3>2R2; or, when the number of elastic members is 2, Such arrangement allows for a better layout of the elastic parts, thereby ensuring the normal operation of the liquid injection function while ensuring the sealing performance.

[0050] In one embodiment, the seal 120 is configured as a metal structural member. In other embodiments, the seal 120 can be a rubber member or the like.

[0051] As shown in FIG. 2 and FIG. 10 , in one embodiment, the sealing top cover 100 further includes a sealing ring 140, which is disposed between the sealing member 120 and the cap 110. The sealing ring 140 can be elastically deformed to seal the gap between the sealing member 120 and the cap 110. By disposing the sealing ring 140 between the sealing member 120 and the cap 110, the gap between the sealing member 120 and the cap 110 can be sealed, thereby further improving the sealing performance of the operation port 111. Specifically, the sealing ring 140 is bonded and fixed to the cap 110. More specifically, a sealing ring positioning groove 112 for positioning the sealing ring 140 is provided on the cap 110, and a portion of the sealing ring 140 is disposed in the sealing ring positioning groove 112. The sealing ring 140 is bonded and fixed to the cap 110 so that the sealing ring 140 cannot be separated from the cap 110. When the injection is completed and no force is applied to the sealing member 120, the sealing member 120 can be pressed against the sealing ring 140 under the elastic force of the spring, thereby maintaining the sealing of the operating port 111.

[0052] In one embodiment, as shown in FIG6 and FIG8, the side surface of the end of the seal 120 facing the cap 110 is configured as an inclined surface, and the diameter of the seal 120 gradually increases from the end facing the cap 110 to the end away from the cap 110. The side surface of the end of the seal 120 facing the cap 110 is configured as an inclined surface, so that the side surface of the seal 120 can press against the sealing ring 140, thereby further improving the sealing performance.

[0053] Specifically, for the cap 110, the inner diameter of the operating port 111 ranges from 7 to 8 mm; the outer diameter of the cap 110 ranges from 19 to 20 mm; the inner diameter of the sealing ring positioning groove for accommodating the sealing ring 140 ranges from 14 to 15 mm; the inner diameter of the accommodating cavity 113 of the cap 110 ranges from 16 to 19 mm, the wall thickness of the cap 110 ranges from 2 to 2.4 mm, and the height of the cap 110 ranges from 5.1 to 6.1 mm; the depth of the accommodating cavity 113 on the cap 110 ranges from 3.6 to 4.1 mm; and the depth of the sealing ring positioning groove 112 ranges from 0.2 to 0.5 mm.

[0054] The outer diameter of the sealing ring 140 is between 14-15 mm, the inner diameter is between 7-8 mm, and the thickness is between 0.6-0.8 mm. The height of the spring is between 2-2.5 mm, the diameter of the spring wire is between 1-1.5 mm, and the outer diameter of the entire spring is between 4-5 mm.

[0055] The minimum diameter of the frustum of the sealing member 120 is in the range of 7-8 mm; the outer diameter of the cylindrical portion is in the range of 14-15 mm, and the overall height is in the range of 2.3-3 mm.

[0056] The utility model also provides a lithium battery, which includes the above-mentioned sealing top cover 100. In one embodiment, the lithium battery also includes a pole 400, which is arranged on the cover plate 200 and protrudes from the cover plate 200, and the distance of the pole 400 protruding from the cover plate 200 is greater than the distance of the cap 110 protruding from the cover plate 200. The height of the cover plate 200 is set to be smaller than the height of the pole 400, so as to avoid changing the structure of the battery cell module due to the sealing top cover 100 being arranged on the cover plate 200.

[0057] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0058] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A sealing top cover for sealing a liquid injection port on a cover plate of a lithium battery, characterized in that: The sealing top cover comprises: A cap is configured to have a receiving cavity with an opening at one end, the cap is disposed at the liquid injection port of the cover plate, and the end surface of the cap is sealed and connected to the cover plate, the cap is configured to have an operation port that passes through the cap in the thickness direction, and the operation port is connected to the receiving cavity and the liquid injection port; A sealing member, disposed in the accommodating cavity; A plurality of elastic members are arranged in the accommodating cavity at intervals, and each of the elastic members is pressed between the sealing member and the cover plate; Wherein, the sealing member seals the operation port under the action of the restoring force of the elastic member; the end of the sealing member facing the operation port can be operably moved toward the direction close to the cover plate to open the operation port.

2. The sealing cover according to claim 1, characterized in that: A plurality of first positioning grooves are arranged on the periphery of the liquid injection port on the cover plate, a plurality of second positioning grooves corresponding to the first positioning grooves are arranged on the end surface of the sealing member facing the cover plate, and both ends of the elastic member are respectively embedded in the first positioning groove and the second positioning groove.

3. The sealing cover according to claim 2, characterized in that: A circle formed by a line connecting the centers of the projections of the plurality of second positioning grooves on the end surface of the seal is concentric with the circle where the end surface of the seal is located.

4. The sealing cover according to claim 3, characterized in that: The outer radius of the seal is defined as R1, the radius of the second positioning groove is defined as R2, and the radius of the projection of the plurality of second positioning grooves on the end surface of the seal is defined as R3, R1>R2+R3; When the number of the elastic members is 3, R3>2R2; Alternatively, when the number of the elastic members is 2, .

5. The sealing cover according to any one of claims 1 to 4, characterized in that: The sealing top cover also includes: A sealing ring is disposed between the sealing member and the cover cap, and the sealing ring can be elastically deformed to seal the gap between the sealing member and the cover cap.

6. The sealing cover according to claim 5, characterized in that: The sealing ring is bonded and fixed to the cover cap.

7. The sealing cover according to claim 5, characterized in that: The seal is configured as a metallic material structure.

8. The sealing cover according to claim 7, characterized in that: The side surface of one end of the sealing member facing the cover cap is configured as an inclined surface, and the diameter of the sealing member gradually increases from the end facing the cover cap to the end away from the cover cap.

9. A lithium battery, characterized in that: The lithium battery comprises a sealing top cover as described in any one of claims 1-8.

10. The lithium battery according to claim 9, characterized in that: The lithium battery further comprises a pole, which is arranged on the cover plate and protrudes from the cover plate, and the distance that the pole protrudes from the cover plate is greater than the distance that the cap protrudes from the cover plate.

Images