Sealing structure and battery cell

Abstract

The utility model relates to battery technical field discloses a kind of sealing structure and electric core, are located in electric core top cover, comprising: plugging element, rotation is located in liquid injection channel;Conversion mechanism, between plugging element and liquid injection channel, conversion mechanism is configured as the rotational motion of plugging element is converted into the linear motion of plugging element along first direction, and plugging element can be switched between first position and second position;In first position, plugging element can seal liquid injection channel;In second position, plugging element can make liquid injection channel and external space conductive. According to actual demand, plugging element can be moved to second position by conversion mechanism, so that liquid injection channel is communicated with external space, at this time, liquid supplementing operation can be carried out, after liquid supplementing is completed, plugging element is moved to first position again by conversion mechanism, i.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a sealing structure and a battery cell. Background Technology

[0002] In the production process of lithium-ion batteries, after the battery has completed the second electrolyte injection, the injection hole must first be sealed with sealing granules, and then a sealing aluminum sheet is welded to the top of the injection hole to achieve a complete seal.

[0003] However, during cell cycling, the electrolyte gradually depletes and decreases. When it reduces to a level where it can no longer effectively wet the electrodes to ensure the smooth migration of lithium ions, lithium plating occurs, leading to a sharp decline in cell cycle life. Therefore, electrolyte replenishment is necessary.

[0004] However, because the electrolyte filling hole uses a sealed structure that is welded to the top cover of the cell, it is impossible to replenish electrolyte as needed in the middle and later stages of the cell's cycle. This results in the battery having to be scrapped or downgraded, which seriously affects the lifespan of the cell. Utility Model Content

[0005] This invention provides a sealing structure and a battery cell to solve or improve the problem in related technologies where the liquid injection hole is sealed by welding a sealing aluminum sheet to the top cover of the battery cell, which makes it impossible to replenish the liquid as needed, thus affecting the service life of the battery cell.

[0006] In a first aspect, this utility model provides a sealing structure disposed on the top cover of a battery cell, the top cover having a liquid injection channel; the sealing structure includes:

[0007] The sealing element is rotatably disposed in the injection channel;

[0008] A conversion mechanism is disposed between the sealing member and the injection channel. The conversion mechanism is configured to convert the rotational motion of the sealing member into linear motion of the sealing member along a first direction, and the sealing member can switch between a first position and a second position. In the first position, the sealing member can seal the injection channel. In the second position, the sealing member can connect the injection channel to the external space.

[0009] In one alternative embodiment, the end of the sealing member is provided with a polygonal countersunk hole, which is adapted to match an installation tool so as to drive the sealing member to rotate under the action of the installation tool.

[0010] In one optional embodiment, the top cover is provided with a communicating support groove and an injection hole to form the injection channel;

[0011] The sealing component includes:

[0012] A support portion is disposed within the support groove;

[0013] The sealing part is connected to the supporting part, and the sealing part is rotatably disposed in the injection hole.

[0014] In one optional implementation, the conversion mechanism includes:

[0015] An external thread section is provided on the outer wall of the sealing part;

[0016] An internal thread section is adapted to the external thread section, and the wall of the injection hole is provided with the internal thread section.

[0017] In one alternative implementation, it further includes:

[0018] The first sealing element is disposed between the support portion and the support groove.

[0019] In one alternative embodiment, one of the support portion and the support groove is provided with a sealing groove, and the first seal is engaged in the sealing groove.

[0020] In one alternative implementation, it further includes:

[0021] An annular stop is provided at one end of the sealing part away from the support part. The annular stop is adapted to abut against or separate from the top cover under the action of the sealing part, and the sealing part is provided with a liquid guiding channel connected to the injection hole.

[0022] The conversion mechanism includes a matching protrusion and a groove. One of the support groove and the support portion is provided with the protrusion, and the other is provided with the groove. The protrusion is inserted into the groove. When the sealing member rotates, it causes the protrusion to retract from the groove and the annular stop to abut against the top cover. The sealing member is in the first position. When the sealing member rotates, it causes the protrusion to insert into the groove and the annular stop to separate from the top cover. The sealing member is in the second position.

[0023] In one alternative implementation, it further includes:

[0024] The second sealing element is sleeved on the sealing part, and the second sealing element is disposed on the side surface of the annular stop facing the top cover.

[0025] In one optional embodiment, the sealing part is provided with a liquid guiding groove that extends through the first direction and is connected to the liquid injection hole, and the supporting part is provided with a liquid guiding hole that extends through the first direction and is connected to the liquid guiding groove to form the liquid guiding channel.

[0026] Secondly, this utility model also provides a battery cell, including the sealing structure described in any of the above claims.

[0027] The sealing structure provided by this utility model allows the sealing component to move to a second position via a conversion mechanism, connecting the liquid injection channel to the external space. This enables smooth liquid replenishment. After replenishment, the sealing component is moved back to the first position via the conversion mechanism to seal the liquid injection channel, ensuring the sealing performance of the cell top cover and restoring the battery to normal operating condition. This effectively overcomes the limitations of traditional liquid injection holes that rely on welded seals, allowing for liquid replenishment at any time as needed, thus ensuring the stability of the cell performance and significantly extending the cell's lifespan. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a cross-sectional view of a sealing structure according to an embodiment of the present utility model;

[0030] Figure 2 This is a schematic diagram of the structure of a sealing component according to an embodiment of the present utility model;

[0031] Figure 3 This is a partial cross-sectional view of an injection channel according to an embodiment of the present utility model;

[0032] Figure 4 This is a cross-sectional view of another sealing structure according to an embodiment of the present utility model;

[0033] Figure 5 This is a second cross-sectional view of another sealing structure according to an embodiment of the present utility model;

[0034] Figure 6 This is a schematic diagram of the structure of another sealing component according to an embodiment of the present utility model;

[0035] Figure 7 This is an exploded view of another sealing component according to an embodiment of the present utility model;

[0036] Figure 8 This is a front view of another sealing component according to an embodiment of the present utility model;

[0037] Figure 9This is a cross-sectional view of another sealing component according to an embodiment of the present utility model;

[0038] Figure 10 This is a partial schematic diagram of another injection channel according to an embodiment of the present utility model.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Top cover; 101. Injection channel; 102. Support groove; 103. Injection hole; 2. Sealing component; 201. Polygonal countersunk hole; 202. Support part; 203. Sealing part; 204. Liquid guiding channel; 205. Liquid guiding hole; 206. Liquid guiding groove; 3. Conversion mechanism; 301. External thread section; 302. Internal thread section; 303. Protrusion; 304. Groove; 4. First sealing component; 5. Sealing groove; 6. Annular stop; 7. Second sealing component. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0042] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0043] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0044] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0045] The following is combined Figures 1 to 10 This describes the sealing structure and battery cell of an embodiment of the present invention.

[0046] According to an embodiment of this utility model, a sealing structure is provided, disposed on the top cover 1 of the battery cell, the top cover 1 having a liquid injection channel 101. Specifically, see... Figures 1 to 10 The sealing structure includes a plugging element 2 and a conversion mechanism 3. Specifically, the plugging element 2 is rotatably disposed in the injection channel 101, and the conversion mechanism 3 is disposed between the plugging element 2 and the injection channel 101. The conversion mechanism 3 is configured to convert the rotational motion of the plugging element 2 into linear motion of the plugging element 2 along a first direction. That is, with the help of the conversion mechanism, the plugging element 2 can perform reciprocating linear motion along the first direction while rotating, thereby enabling the opening or closing of the injection channel 101. Moreover, the plugging element 2 can switch between a first position and a second position. When the plugging element 2 is in the first position, it can seal the injection channel 101, thereby achieving a seal on the top cover 1. When the plugging element 2 is in the second position, it can connect the injection channel 101 to the external space, thereby allowing electrolyte to be added into the injection channel 101.

[0047] This configuration allows the sealing element 2 to move to the second position via the conversion mechanism 3, connecting the liquid injection channel 101 to the external space, enabling smooth liquid replenishment. After replenishment, the sealing element 2 is moved back to the first position via the conversion mechanism 3, sealing the liquid injection channel 101 and ensuring the sealing performance of the cell top cover 1, thus restoring the battery to normal operating condition. This effectively overcomes the limitations of traditional liquid injection holes that rely on welded seals, allowing for liquid replenishment at any time according to actual needs, thereby ensuring the stability of cell performance and significantly extending the cell's lifespan.

[0048] Optionally, in some embodiments of this utility model, such as Figure 2 and Figure 8 As shown, the end of the sealing component 2 is provided with a polygonal countersunk hole 201. The polygonal countersunk hole 201 is adapted to match the installation tool so that the sealing component 2 can be rotated under the action of the installation tool. Specifically, taking a hexagonal countersunk hole 201 as an example, the installation tool can be a matching hexagonal wrench, which can drive the sealing component 2 to rotate. This design, which uses a polygonal countersunk hole 201 that matches the installation tool, can effectively improve the convenience of fluid replenishment operation, and the countersunk hole design improves the compactness of the overall structure.

[0049] Optionally, in some embodiments of this utility model, such as Figure 3 and Figure 10 As shown, the top cover 1 is provided with a connected support groove 102 and an injection hole 103 to form an injection channel 101. Figure 2 and Figure 9 As shown, the sealing component 2 includes a support portion 202 and a sealing portion 203 connected to each other. For example, the two can be designed as a single piece to improve processing efficiency and structural performance. The support portion 202 is disposed within the support groove 102, and the sealing portion 203 is rotatably disposed within the injection hole 103. This arrangement provides stable support for the sealing component 2, ensuring reliable engagement between the sealing component 2 and the top cover 1, effectively preventing the sealing component 2 from accidentally falling into the battery cell, and the sealing component 2 does not occupy additional space, making the battery cell structure more compact.

[0050] Optionally, in some embodiments of this utility model, see Figures 1 to 3 The conversion mechanism 3 includes a matching external thread section 301 and an internal thread section 302. For example... Figure 2 As shown, the outer wall of the sealing part 203 is provided with an external thread section 301, such as... Figure 3As shown, the injection hole 103 has an internal thread section 302 on its wall, thereby allowing the sealing member 2 to be installed on the top cover 1 via a threaded connection. Optionally, the sealing member 2 may be a metal component such as an aluminum nail. Of course, in some other embodiments, to avoid stripping due to repeated disassembly and assembly, and to prevent the generation of metal wires that could cause short circuits in the battery cell, the sealing member 2 may be made of a rigid plastic material instead of a metal material. It is recommended that the hardness of the rigid plastic material be greater than 70 HRC to ensure its reliability.

[0051] It should be noted that, as Figure 1 As shown, when replenishing electrolyte as needed, screw on the sealing component 2. With the threaded connection, the sealing component 2 moves upwards until it is removed. At this point, the electrolyte injection channel 101 opens, allowing for electrolyte replenishment. After replenishment, screw the sealing component 2 back into the electrolyte injection hole 103 to seal the electrolyte injection channel 101, achieving a sealed connection to the top cover 1 and preventing electrolyte overflow. This design features a simple overall structure, convenient operation, and allows for rapid electrolyte replenishment, ensuring the cell's cycle performance.

[0052] Optionally, in some embodiments of this utility model, such as Figure 1 As shown, the sealing structure also includes a first sealing element 4, which is disposed between the support portion 202 and the support groove 102. Optionally, the first sealing element 4 is an O-ring or similar seal, and the sealing compression of the seal can be between 10% and 40%. With this configuration, the sealing performance between the plugging component 2 and the injection channel 101 can be further improved by the first sealing element 4, effectively preventing electrolyte overflow.

[0053] Optionally, in some embodiments of this utility model, one of the support portion 202 and the support groove 102 is provided with a sealing groove 5, and the first sealing member 4 is engaged in the sealing groove 5. That is, the support groove 102 is provided with a sealing groove 5, or the support portion 202 is provided with a sealing groove 5. For example, as Figure 1 As shown, the bottom wall of the support groove 102 is provided with a sealing groove 5, and the first sealing element 4 is snapped into the sealing groove 5. This provides precise installation positioning for the first sealing element 4, preventing it from shifting due to external forces such as vibration during assembly or use, and improving the reliability of the seal. In addition, in some embodiments, the bottom wall of the support groove 102 may be provided with multiple sealing grooves 5 at intervals, with the first sealing element 4 corresponding to each sealing groove 5, thereby forming multiple seals and improving the sealing effect.

[0054] Optionally, in some embodiments of this utility model, such as Figure 6As shown, the sealing structure also includes an annular stop 6, which is disposed at one end of the sealing part 203 away from the support part 202. For example, it is fixed by means of threaded connection, snap-fit, welding or other connection methods. The annular stop 6 is adapted to abut or separate from the top cover 1 under the action of the sealing part 2, and the sealing part 2 is provided with a liquid guiding channel 204 communicating with the injection hole 103.

[0055] like Figure 4 As shown, the conversion mechanism 3 includes a matching protrusion 303 and a groove 304. One of the support groove 102 and the support portion 202 has a protrusion 303, and the other has a groove 304. The protrusion 303 is inserted into the groove 304. That is, the support portion 202 has a protrusion 303, and the support groove 102 has a corresponding groove 304; or, the support groove 102 has a protrusion 303, and the support portion 202 has a corresponding groove 304. For example, as... Figure 7 As shown, the support portion 202 is provided with a protrusion 303, such as Figure 10 As shown, the support groove 102 is provided with a matching groove 304. Optionally, there are multiple grooves 304, which are distributed circumferentially around the injection hole 103, and the protrusions 303 are provided in a one-to-one correspondence with the grooves 304. The protrusions 303 can be arc-shaped protrusions, and the grooves are arc-shaped grooves adapted to the arc-shaped protrusions, so that the protrusions 303 can slide smoothly into or out of the grooves 304.

[0056] It should be noted that, as Figure 4 As shown, when the sealing member 2 rotates at a certain angle, it causes the protrusion 303 to exit from the groove 304, making the sealing member 2 move upward and causing the annular stop 6 to abut against the top cover 1. At this time, the sealing member 2 is in the first position, and the sealing member 2 seals the injection channel 101. Figure 5 As shown, when the sealing member 2 rotates at a certain angle, it causes the protrusion 303 to insert into the groove 304, making the sealing member 2 move downwards and causing the annular stop 6 to separate from the top cover 1, i.e., when there is a gap between the two, the sealing member 2 is in the second position. At this time, the electrolyte can be injected smoothly, and the electrolyte flow path is as follows. Figure 5 The direction indicated by the middle arrow.

[0057] With this configuration, by rotating the sealing component 2 and utilizing the snap-fit ​​between the protrusion 303 and the groove 304, the vertical displacement of the sealing component 2 is achieved, thereby changing the on / off state of the liquid injection channel 101, thus realizing the liquid replenishment function in the later stages of the cell cycle and improving the reliability of the cell cycle life.

[0058] Furthermore, in other embodiments, such as Figure 4As shown, when the sealing member 2 rotates at a certain angle, causing the protrusion 303 to exit from the groove 304, the sealing member 2 moves upward and causes the annular stop 6 to abut against the top cover 1. A limiting part adapted to the protrusion 303 can also be provided to ensure that the sealing member 2 remains stably in the first position, improving the reliability of the seal. Optionally, taking the support part 202 with the protrusion 303 as an example, the limiting part is a slot provided on the support groove 102, where the protrusion 303 is engaged. It should be noted that the depth of the slot should be less than the depth of the groove 304 to ensure that the sealing member 2 can reliably contact the annular stop 6 with the top cover 1, ensuring a sealing effect.

[0059] Optionally, in some embodiments of this utility model, such as Figure 4 and Figure 5 As shown, the sealing structure also includes a second sealing element 7, which is sleeved on the sealing portion 203 and disposed on the surface of the annular stop 6 facing the top cover 1, so that the second sealing element 7 can accurately seal the gap between the annular stop 6 and the top cover 1. Optionally, the second sealing element 7 is an O-ring or similar sealing ring, and the sealing compression of the sealing ring can be between 10% and 40%. With this configuration, the sealing effect between the annular stop 6 and the top cover 1 can be effectively improved by compressing the second sealing element 7, ensuring that the electrolyte does not leak out and improving the reliability and safety of the battery cell.

[0060] Optionally, in some embodiments of this utility model, such as Figure 5 and Figure 7 As shown, the sealing part 203 is provided with a liquid guiding groove 206 that extends through the first direction and communicates with the injection hole 103. Specifically, the liquid guiding groove 206 can be provided on the outer surface of the sealing part 203, or it can be provided inside the sealing part 203. For example, as Figure 7 As shown, a liquid guiding groove 206 is disposed on the outer surface of the sealing part 203. The support part 202 is provided with a liquid guiding hole 205 extending along a first direction, and the liquid guiding hole 205 is connected to the liquid guiding groove 206 to form a liquid guiding channel 204. Optionally, there are multiple liquid guiding grooves 206, each distributed at intervals along the circumference of the sealing part 203, and the liquid guiding holes 205 and liquid guiding grooves 206 are arranged in a one-to-one correspondence to improve the liquid replenishment efficiency. With this arrangement, the liquid guiding holes 205 and liquid guiding grooves 206 cooperate to form a guiding channel connected to the injection hole 103, meeting the subsequent requirements for battery cell liquid replenishment. Furthermore, in other embodiments, such as... Figure 8 As shown, a protective film can also be placed over the end of the liquid guiding hole 205 to block the liquid guiding hole 205, thereby preventing contamination of the liquid injection passage during use.

[0061] According to an embodiment of the present invention, another aspect provides a battery cell including the sealing structure as described in the various embodiments above. The derivation process of this beneficial effect is roughly similar to the derivation process of the beneficial effect of the sealing structure described above, and therefore will not be repeated here.

[0062] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A sealing structure, characterized in that, The top cover (1) of the battery cell is provided with a liquid injection channel (101); the sealing structure includes: The sealing element (2) is rotatably disposed in the injection channel (101); A conversion mechanism (3) is disposed between the sealing member (2) and the injection channel (101). The conversion mechanism (3) is configured to convert the rotational motion of the sealing member (2) into linear motion of the sealing member (2) along a first direction, and the sealing member (2) can switch between a first position and a second position. In the first position, the sealing member (2) can seal the injection channel (101). In the second position, the sealing member (2) can connect the injection channel (101) to the external space.

2. The sealing structure according to claim 1, characterized in that, The end of the sealing member (2) is provided with a polygonal countersunk hole (201), which is adapted to match the installation tool so as to drive the sealing member (2) to rotate under the action of the installation tool.

3. The sealing structure according to claim 1 or 2, characterized in that, The top cover (1) is provided with a connected support groove (102) and a liquid injection hole (103) to form the liquid injection channel (101); The sealing element (2) includes: A support portion (202) is disposed within the support groove (102); The sealing part (203) is connected to the support part (202), and the sealing part (203) is rotatably disposed in the injection hole (103).

4. The sealing structure according to claim 3, characterized in that, The conversion mechanism (3) includes: An external thread section (301) is provided on the outer wall of the sealing part (203); The internal thread section (302) is adapted to the external thread section (301), and the wall of the injection hole (103) is provided with the internal thread section (302).

5. The sealing structure according to claim 4, characterized in that, Also includes: The first sealing element (4) is disposed between the support portion (202) and the support groove (102).

6. The sealing structure according to claim 5, characterized in that, One of the support part (202) and the support groove (102) is provided with a sealing groove (5), and the first sealing member (4) is engaged in the sealing groove (5).

7. The sealing structure according to claim 3, characterized in that, Also includes: An annular stop (6) is provided at one end of the sealing part (203) away from the support part (202). The annular stop (6) is adapted to abut or separate from the top cover (1) under the action of the sealing part (2). The sealing part (2) is provided with a liquid guiding channel (204) connected to the injection hole (103). The conversion mechanism (3) includes a matching protrusion (303) and a groove (304). One of the support groove (102) and the support part (202) is provided with the protrusion (303) and the other is provided with the groove (304). The protrusion (303) is inserted into the groove (304). When the sealing member (2) rotates and drives the protrusion (303) to exit from the groove (304) and drives the annular stop (6) to abut against the top cover (1), the sealing member (2) is in the first position. When the sealing member (2) rotates and drives the protrusion (303) to insert into the groove (304) and drives the annular stop (6) to separate from the top cover (1), the sealing member (2) is in the second position.

8. The sealing structure according to claim 7, characterized in that, Also includes: The second sealing element (7) is sleeved on the sealing part (203), and the second sealing element (7) is disposed on the side surface of the annular stop (6) facing the top cover (1).

9. The sealing structure according to claim 7, characterized in that, The sealing part (203) is provided with a liquid guiding groove (206) that extends through the first direction and is connected to the liquid injection hole (103). The support part (202) is provided with a liquid guiding hole (205) that extends through the first direction and is connected to the liquid guiding groove (206) to form the liquid guiding channel (204).

10. A battery cell, characterized in that, Includes the sealing structure as described in any one of claims 1 to 9.

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