Sealing assembly of cylindrical lithium battery cap

Abstract

The utility model discloses a sealing assembly of a cylindrical lithium battery cap, which belongs to the technical field of cylindrical lithium batteries and comprises a top cover and an elastic piece sleeved in the top cover and used for current transmission, and an elastic sealing ring used for enhancing sealing performance is sleeved outside the elastic piece. The elastic sealing ring is sleeved with a sealing piece used for sealing a gap between the top cover and the elastic sealing ring. According to the utility model, structures such as the elastic piece, the sealing piece, the bottom supporting piece and the elastic sealing ring are matched for use, when the top cover is sealed and pressed on the cylindrical lithium battery shell, the elastic sealing ring is expanded under the elastic deformation of the elastic conductive ring and the supporting piece under the pushing of pressure, so that the sealing lantern ring is supported and deformed, and the sealing effect is improved. The sealing strength between the sealing sleeve ring and the top cover, the sealing strength between the middle partition sealing ring and the bottom tray, the sealing piece and the shell and the sealing strength between the electrode column and the electrode column hole are improved, the sealing comprehensiveness is improved, and the problem of waste gas leakage which influences the cylindrical lithium battery is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of cylindrical lithium batteries, in particular to a sealing component of a cylindrical lithium battery cap. Background Art

[0002] Lithium batteries are widely used in small electrical appliances and new energy vehicles. They are generally cylindrical and their size specifications vary with different applications, but their main structures are the same or similar, consisting of a top cover, a non-aqueous electrolyte, and positive and negative electrodes. During the production and processing of cylindrical lithium batteries, it is necessary to maintain good sealing between the top cover and the main body to prevent leakage of the non-aqueous electrolyte and cause environmental pollution or fire hazards. The top cover seals of existing cylindrical lithium batteries are generally concentrated around the poles, resulting in relatively poor sealing at the top cover boundary, which makes the sealing here also susceptible to the impact of the shell wrapping process.

[0003] The existing patent application number: 202122565189.7 discloses a cylindrical power lithium battery top cover structure with reliable sealing. The device can avoid the risk of air leakage, maintain good airtightness, and improve the reliability of sealing. The upper and lower plastics play a buffering role in riveting, which is beneficial to protecting the top cover sheet. In the above-mentioned prior art, the device still has the above-mentioned technical problems during assembly and use. Utility Model Content

[0004] The purpose of the utility model is to provide a sealing assembly for a cylindrical lithium battery cap, so as to solve the problem that the top cover seal proposed in the above-mentioned background technology is easily concentrated around the pole when it is set, resulting in relatively poor sealing at the top cover boundary, and the outer shell wrapping processing is also easy to affect the sealing at the top cover boundary.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] The utility model provides a sealing assembly for a cylindrical lithium battery cap, comprising a top cover and an elastic member for current transmission sleeved inside the top cover, the elastic member is sleeved outside with an elastic sealing ring for enhancing sealing performance, the elastic sealing ring is sleeved outside with a sealing member for sealing the gap between the top cover and the elastic sealing ring, the sealing member is sleeved inside with a bottom support member for explosion prevention, and the elastic member comprises:

[0007] An electrode column plugged into the electrode hole provided on the top cover.

[0008] An electrode top block fixed on the electrode column for plugging the electrode column hole.

[0009] A plurality of support sheets are fixed on the electrode top block.

[0010] A wedge-shaped strip fixed on the supporting sheet for pushing open the elastic sealing annular variable.

[0011] An elastic conductive ring fixed on the electrode top block.

[0012] The sealing element comprises:

[0013] A sealing ring is arranged between the top cover and the bottom support member, and the sealing ring is used to seal the gap between the top cover and the bottom support member.

[0014] A septum sealing ring is fixed in the sealing ring, and the septum sealing ring divides the sealing ring into two upper and lower annular limiting grooves.

[0015] The elastic sealing ring comprises:

[0016] An elastic collar is sleeved in one of the annular limiting grooves, wherein an annular slot for limiting and fixing the wedge strip is arranged in the elastic collar.

[0017] A wedge-shaped stop block is fixed on the elastic sleeve ring, and the wedge-shaped stop block is located at the upper edge of the elastic sleeve ring.

[0018] Furthermore, the top cover includes an upper convex cover and a stepped annular groove arranged in the upper convex cover.

[0019] Furthermore, the electrode top block is sleeved in the stepped annular groove, and the top of the electrode top block is in close contact with the inner wall of the stepped annular groove.

[0020] Furthermore, the opposing surfaces of the wedge-shaped strip and the wedge-shaped stop block are both inclined surfaces, and the inclined surface on the wedge-shaped strip matches the inclined surface on the wedge-shaped stop block.

[0021] Furthermore, the bottom support comprises:

[0022] A bottom tray is sleeved in the remaining annular limiting groove, and a through hole is provided at the center of the bottom tray.

[0023] A reinforcement ring is fixed on the bottom tray, and a reinforcement groove opened outward is formed between the reinforcement ring and the bottom tray.

[0024] Furthermore, the bottom tray is in an inverted truncated cone shape, and the elastic conductive ring passes through the through hole.

[0025] Compared with the prior art, one or more of the above technical solutions have the following beneficial effects:

[0026] 1. The utility model uses the elastic member, the sealing member, the bottom support member and the elastic sealing ring and other structures in coordination with each other. When the top cover is sealed and pressed onto the cylindrical lithium battery shell, the elastic conductive ring and the support sheet are elastically deformed under the push of pressure, and the elastic sealing ring is stretched open, so that the sealing ring is supported and deformed, thereby increasing the sealing strength between the sealing ring and the top cover, the middle septum sealing ring and the bottom tray, the sealing member and the shell, and the electrode column and the electrode column hole, thereby improving the comprehensiveness of the sealing, avoiding the problem of exhaust gas leakage, and affecting the cylindrical lithium battery;

[0027] 2. The utility model forms an annular groove by reinforcing the boundary between the ring and the bottom tray. When the cylindrical lithium battery shell and the top cover are pressurized and assembled, the shell at the groove can be deformed and sunken into the groove through the ring pressing operation, thereby further increasing the sealing effect and sealing strength between the sealing assembly and the shell, and improving the battery's resistance to expansion. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is an axonometric drawing of the utility model;

[0029] Figure 2 It is a half-section diagram of the utility model;

[0030] Figure 3 It is a half-section view of the top cover in the utility model;

[0031] Figure 4 It is an axonometric view of the elastic member in the utility model;

[0032] Figure 5 It is a half-section diagram of the sealing member in the utility model;

[0033] Figure 6 It is an axonometric view of the bottom support member of the utility model;

[0034] Figure 7 It is a half-section view of the elastic sealing ring in the utility model.

[0035] In the figure: 1. top cover; 11. upper convex cover; 12. stepped annular groove; 2. elastic member; 21. electrode column; 22. electrode top block; 23. elastic conductive ring; 24. support sheet; 25. wedge strip; 3. sealing member; 31. sealing collar; 32. septum sealing ring; 33. annular limiting groove; 4. bottom support member; 41. bottom tray; 42. reinforcement ring; 43. reinforcement groove; 44. through hole; 5. elastic sealing ring; 51. elastic collar; 52. annular slot; 53. wedge-shaped stop block; 6. pole hole. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0037] like Figures 1 to 7 As shown, a sealing assembly of a cylindrical lithium battery cap includes a top cover 1 and an elastic member 2 for current transmission sleeved in the top cover 1, an elastic sealing ring 5 for enhancing sealing is sleeved on the outside of the elastic member 2, a sealing member 3 for sealing the gap between the top cover 1 and the elastic sealing ring 5 is sleeved on the outside of the elastic sealing ring 5, a bottom support member 4 for explosion prevention is sleeved inside the sealing member 3, and the elastic member 2 includes:

[0038] The electrode column 21 is plugged into the electrode hole 6 provided on the top cover 1 .

[0039] The electrode top block 22 is fixed on the electrode column 21 and used for blocking the electrode column hole 6.

[0040] A plurality of support sheets 24 are fixed on the electrode top block 22. The support sheets 24 are made of insulating, elastic and tough materials. When assembled between the cylindrical lithium battery housing and the top cover 1, the pressure on the top cover 1 is transmitted to the support sheets 24, so that the plurality of support sheets 24 are elastically deformed at the same time, extend radially outward along the top cover 1, and reduce their height in the vertical direction.

[0041] The wedge-shaped strip 25 fixed on the support sheet 24 is used to push open the deformation of the elastic sealing ring 5. When the support sheet 24 is subjected to pressure, it will extend outward and reduce its height, so as to facilitate pushing the wedge-shaped strip 25 into the elastic sealing ring 5 by a certain distance, so that the elastic sealing ring 5 and the seal 3 are spread out to a certain height in the vertical direction, thereby increasing the sealing between the top cover 1 and the seal 3, and the seal 3 and the elastic sealing ring 5, and the resistance to the internal pressure of the cylindrical lithium battery, and reducing the probability of exhaust gas leakage.

[0042] The elastic conductive ring 23 fixed on the electrode top block 22 will undergo elastic deformation under the pressure exerted on the top cover 1 when assembled between the top cover 1 and the cylindrical lithium battery casing, and make its bottom contact with the positive electrode of the battery cell, thereby improving its good contact with the positive electrode and avoiding the problem of poor contact caused by external force, which affects the safety of the cylindrical lithium battery.

[0043] The seal 3 comprises:

[0044] A sealing collar 31 is provided between the top cover 1 and the bottom support member 4 , and is used for sealing the gap between the top cover 1 and the bottom support member 4 .

[0045] The septum sealing ring 32 is fixed in the sealing ring 31 , and the septum sealing ring 32 divides the sealing ring 31 into two upper and lower annular limiting grooves 33 .

[0046] The elastic sealing ring 5 comprises:

[0047] An elastic collar 51 is sleeved in one of the annular limiting grooves 33 , and an annular slot 52 for limiting and fixing the wedge strip 25 is arranged in the elastic collar 51 .

[0048] The wedge-shaped stopper 53 is fixed on the elastic ring 51 and is located at the upper edge of the elastic ring 51. The elastic ring 51 will expand the opening of the annular slot 52 under the pressure of the wedge strip 25, so as to expand the opening of the corresponding annular limiting groove 33, thereby improving the extrusion strength between the top of the sealing ring 31 and the top cover 1, and improving the sealing between the two.

[0049] In this embodiment, the top cover 1 includes an upper convex cover 11 and a stepped annular groove 12 provided in the upper convex cover 11. The upper convex cover 11 is designed to be convex in shape so as to improve its supporting strength in the vertical direction and its pressure resistance during the assembly process of the cylindrical lithium battery, so as to avoid deformation thereof and thus affect the normal use of the cylindrical lithium battery.

[0050] In this embodiment, the electrode top block 22 is inserted into the stepped annular groove 12, and the top of the electrode top block 22 is in close contact with the inner wall of the stepped annular groove 12. During the assembly of the cylindrical lithium battery, the elastic force provided by the elastic deformation of the support sheet 24 and the elastic conductive ring 23 is utilized to strengthen the extrusion sealing shape of the contact surface between the electrode top block 22 and the stepped annular groove 12, thereby preventing the two from easily separating and affecting the sealing effect.

[0051] In this embodiment, the opposing surfaces of the wedge strip 25 and the wedge stop 53 are both inclined surfaces, and the inclined surface on the wedge strip 25 matches the inclined surface on the wedge stop 53. The inclined surfaces on the two surfaces press against each other under the action of elastic force, thereby improving the sealing effect between the contacting surfaces of the two surfaces.

[0052] In this embodiment, the bottom support member 4 includes:

[0053] The bottom tray 41 is mounted in the remaining annular limiting groove 33 , and a through hole 44 is provided at the center of the bottom tray 41 .

[0054] A reinforcement ring 42 is fixed on the bottom tray 41, and a reinforcement groove 43 open outward is formed between the reinforcement ring 42 and the bottom tray 41. When the cylindrical lithium battery shell and the top cover 1 are assembled and fixed, a circumferential concave pressing operation can be performed at a position corresponding to the reinforcement groove 43 on the shell, so that the shell is recessed into the reinforcement groove 43 at this point, which can further increase the fixing firmness between the shell and the top cover 1, and can also add an extra sealing layer, further increasing the sealing between the top cover 1 and the shell.

[0055] In this embodiment, the bottom tray 41 is in the shape of an inverted truncated cone, and the elastic conductive ring 23 passes through the through hole 44, which is convenient for transmitting the power stored in the battery cell to the outside, or transmitting external power to the battery cell to accumulate power during charging.

[0056] The above description is only the preferred embodiment of the utility model, and the parts not described in the utility model can be implemented by adopting or drawing on existing technologies. Of course, the above description is not a limitation of the utility model, and the utility model is not limited to the above examples. The changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the utility model should also fall within the protection scope of the utility model.

Claims

1. A sealing assembly for a cylindrical lithium battery cap, comprising a top cover (1) and an elastic member (2) for current transmission sleeved inside the top cover (1), an elastic sealing ring (5) for enhancing sealing performance sleeved outside the elastic member (2), a sealing member (3) for sealing a gap between the top cover (1) and the elastic sealing ring (5) sleeved outside the elastic sealing ring (5), an explosion-proof bottom support member (4) sleeved inside the sealing member (3), characterized in that: The elastic member (2) comprises: An electrode column (21) plugged into a pole hole (6) provided on the top cover (1); An electrode top block (22) fixed on the electrode column (21) and used for sealing the electrode column hole (6); A plurality of support sheets (24) fixed on the electrode top block (22); A wedge-shaped strip (25) fixed on the support sheet (24) and used to push the elastic sealing ring (5) to deform; An elastic conductive ring (23) fixed on the electrode top block (22); The sealing element (3) comprises: a sealing collar (31) disposed between the top cover (1) and the bottom support member (4), the sealing collar (31) being used to seal a gap between the top cover (1) and the bottom support member (4); A septum sealing ring (32) fixed in the sealing ring (31), wherein the septum sealing ring (32) divides the sealing ring (31) into two upper and lower annular limiting grooves (33); The elastic sealing ring (5) comprises: An elastic sleeve (51) sleeved in one of the annular limiting grooves (33), wherein an annular slot (52) for limiting and fixing the wedge-shaped strip (25) is provided in the elastic sleeve (51); A wedge-shaped stopper (53) is fixed on the elastic sleeve ring (51), and the wedge-shaped stopper (53) is located at the upper edge of the elastic sleeve ring (51).

2. The sealing assembly of the cylindrical lithium battery cap according to claim 1, characterized in that: The top cover (1) comprises an upper convex cover (11) and a stepped annular groove (12) provided in the upper convex cover (11).

3. The sealing assembly of the cylindrical lithium battery cap according to claim 2, characterized in that: The electrode top block (22) is sleeved in the stepped annular groove (12), and the top of the electrode top block (22) is in tight contact with the inner wall of the stepped annular groove (12).

4. The sealing assembly of the cylindrical lithium battery cap according to claim 3, characterized in that: The opposing surfaces of the wedge-shaped strip (25) and the wedge-shaped stop block (53) are both inclined surfaces, and the inclined surface on the wedge-shaped strip (25) matches the inclined surface on the wedge-shaped stop block (53).

5. The sealing assembly of the cylindrical lithium battery cap according to claim 4, characterized in that: The bottom support member (4) comprises: A bottom tray (41) is mounted in the remaining annular limiting groove (33), wherein a through hole (44) is provided at the center of the bottom tray (41); A reinforcement ring (42) is fixed on the bottom tray (41), and the reinforcement ring (42) and the bottom tray (41) are combined to form a reinforcement groove (43) that is open outwards.

6. The sealing assembly of the cylindrical lithium battery cap according to claim 5, characterized in that: The bottom tray (41) is in the shape of an inverted truncated cone, and the elastic conductive ring (23) passes through the through hole (44).

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