A high-safety cylindrical combination cap

Abstract

This utility model relates to the field of battery cell cap technology, and discloses a high-safety cylindrical composite cap, including a top cover, an explosion-proof sheet, a sealing assembly, a positive electrode connecting piece, an insulating pad, and an insulating isolation plate and a buffer pad for preventing internal short circuits of the battery cell. The top cover is located at the top, the explosion-proof sheet is located below the top cover and is fixedly connected to the top cover, and the sealing assembly is located below the explosion-proof sheet and fits tightly with the outer shell of the cylindrical battery. This high-safety cylindrical composite cap uses a sealing assembly including a rubber sealing ring and an elastic metal sealing ring. The sealing ring is tightly fitted onto the top edge of the cylindrical battery shell, effectively filling the tiny gaps between the shell and the cap. The sealing ring is located above the sealing ring and fits tightly with the explosion-proof sheet. The elasticity of the metal further enhances the sealing effect, effectively preventing external moisture and impurities from entering the battery, avoiding performance degradation and shortened lifespan due to contamination, and also preventing leakage of electrolyte inside the battery.

Description

Technical Field

[0001] This utility model relates to the field of battery cell cap technology, and in particular to a high-safety cylindrical combination cap. Background Technology

[0002] In the field of modern energy applications, especially in energy storage devices represented by lithium-ion batteries, cylindrical batteries have been widely used in digital devices such as laptops, digital cameras, and mobile phones, as well as large-scale application scenarios such as electric vehicles, bicycles, mobile base stations, and energy storage base stations, due to their unique advantages, such as good space adaptability and ease of combination into battery packs. Against this background, the use of batteries is no longer limited to individual presentation, but more often they are connected in series or parallel to form battery packs to meet the diverse needs of different devices for power and performance.

[0003] However, existing high-safety cylindrical combination caps have the following drawbacks: (1) Traditional cylindrical battery caps often become loose due to a single sealing design. This can lead to external moisture and dust entering the battery, contaminating the electrode materials and electrolyte, resulting in reduced capacity and shortened cycle life. (2) If the traditional explosion-proof sheet is not equipped with a directional structure, the high-pressure gas is prone to disorderly jetting and impacting the surrounding components, resulting in chain damage to the battery pack. Furthermore, some explosion-proof holes may break unexpectedly under pressure fluctuations during normal use due to insufficient structural strength, or may fail to open in time under real high pressure, posing a risk of false triggering or failure. (3) In the charging, discharging, transportation or vibration environment, the positive electrode connecting piece of the cylindrical battery may be displaced due to loose fixing, or may rub or collide with the battery cell, resulting in damage to the insulation layer and causing internal short circuit.

[0004] Therefore, this utility model provides a high-safety cylindrical combination cap. Utility Model Content

[0005] (a) Technical problems to be solved The problem solved by this utility model is to provide a highly practical and safe cylindrical combination cap, which solves the problems mentioned in the background art, such as the single sealing design of cylindrical battery caps, the easy disorderly jetting of high-pressure gas impacting the surrounding components, leading to chain damage to the battery pack, and the possibility of displacement of the positive electrode connecting piece due to loose fixing.

[0006] (II) Technical Solution To achieve the above objectives, this utility model provides the following technical solution: a high-safety cylindrical composite cap, comprising a top cover, an explosion-proof sheet, a sealing assembly, a positive electrode connecting piece, an insulating pad, and an insulating isolation plate and a buffer pad for preventing internal short circuits of the battery cell. The top cover is located at the top, the explosion-proof sheet is disposed below the top cover and fixedly connected to it, the sealing assembly is disposed below the explosion-proof sheet and tightly fitted with the outer casing of the cylindrical battery, the positive electrode connecting piece passes through the top cover and the explosion-proof sheet and is connected to the positive electrode of the battery cell, and the insulating pad is disposed between the positive electrode connecting piece and the top cover and the explosion-proof sheet.

[0007] Optionally, the sealing assembly includes a sealing ring and a sealing ring. The sealing ring is made of rubber and is fitted onto the top edge of the cylindrical battery casing. The sealing ring is positioned above the sealing ring and fits tightly against the explosion-proof sheet. The sealing ring is made of metal. The double sealing of the sealing ring and the sealing ring effectively improves the overall sealing reliability and reduces the risk of electrolyte leakage and external contamination.

[0008] Optionally, the explosion-proof sheet has multiple explosion-proof holes, which are elliptical in shape. The edges of the explosion-proof holes are provided with flanges that protrude to one side. The flanges on the edges of the explosion-proof holes protrude to one side, which can guide the gas to be discharged in a specific direction. At the same time, the flange structure enhances the strength of the edges of the explosion-proof holes, ensuring the stability and safety of the explosion-proof function.

[0009] Optionally, the insulating separator is disposed between the battery cell and the positive electrode connecting piece, and the buffer pad is disposed on the side of the insulating separator closer to the battery cell. The buffer pad is made of rubber. The insulating separator physically isolates and blocks the path of direct contact between the two, while the rubber buffer pad can absorb vibration and impact during battery use. This dual protection significantly reduces the risk of internal short circuit.

[0010] Optionally, the top cover is equipped with a connection terminal for connecting to an external circuit. The connection terminal is connected to the positive electrode connecting piece through a conductive connector. The conductive connector is made of copper. The connection terminal provides a standardized interface for connecting to the external circuit, simplifying the connection process between the battery and external devices. The copper conductive connector connects the connection terminal and the positive electrode connecting piece, which can reduce resistance loss during current transmission.

[0011] Optionally, the insulating pad has a perforation adapted to the positive electrode connecting piece. The inner wall of the perforation is provided with an insulating coating, which is a polytetrafluoroethylene coating. The perforation ensures that the positive electrode connecting piece can pass through smoothly, and the insulating pad itself isolates the positive electrode connecting piece from the top cover and the explosion-proof sheet. The polytetrafluoroethylene is used to further enhance the insulation effect and improve electrical safety performance.

[0012] Optionally, the cylindrical combination cap also includes a protective cover disposed on the top cover. The protective cover is made of plastic and is detachably connected to the top cover by a buckle. The plastic protective cover covers the top cover and can prevent external dust, water droplets and other contaminants from contacting the top cover and connecting terminals, thus providing protection. The detachable connection with the top cover by the buckle facilitates quick disassembly and installation, making it convenient to inspect or replace the top cover and related components, and extending the service life of the cap.

[0013] Optionally, an annular pressure relief channel is provided between the top cover and the explosion-proof sheet. The pressure relief channel is connected to the explosion-proof hole on the explosion-proof sheet. The inner wall of the pressure relief channel is provided with a high-temperature resistant coating. The annular pressure relief channel is connected to the explosion-proof hole on the explosion-proof sheet, providing a dedicated flow channel for the gas discharged from the explosion-proof hole, avoiding the accumulation of gas between the top cover and the explosion-proof sheet and the generation of local high pressure. The high-temperature resistant coating enhances the reliability of the explosion-proof system.

[0014] (III) Beneficial Effects This utility model provides a high-safety cylindrical combination cap, which has the following beneficial effects: 1. This high-safety cylindrical combination cap uses a sealing assembly including a rubber sealing ring and an elastic metal sealing ring. The sealing ring is tightly fitted onto the top edge of the cylindrical battery casing, effectively filling the tiny gaps between the casing and the cap. The sealing ring is positioned above the sealing ring and fits tightly against the explosion-proof sheet. The elasticity of the metal further enhances the sealing effect, effectively preventing external moisture and impurities from entering the battery, avoiding performance degradation and shortened lifespan due to contamination. It also prevents leakage of electrolyte inside the battery, reducing safety risks.

[0015] 2. This high-safety cylindrical combination cap features a specially shaped explosion-proof hole with a raised flange on one side. When the internal pressure of the battery rises due to abnormal conditions, gas can be quickly discharged through the explosion-proof hole. The flange structure guides the direction of gas discharge, avoiding impact on surrounding components. It also increases the structural strength of the explosion-proof hole, preventing accidental breakage during normal use and ensuring reliable opening at critical moments, thus protecting the safety of the battery and the operating environment.

[0016] 3. This high-safety cylindrical combination cap features an insulating isolation plate positioned between the battery cell and the positive electrode connector. This physically isolates the two, preventing short circuits caused by direct contact between the positive electrode connector and the battery cell due to displacement or other reasons. The sponge or rubber buffer pad located near the battery cell absorbs vibrations and impacts generated during battery use, preventing damage to the insulation layer caused by friction and collision between the battery cell and the positive electrode connector, which could lead to a short circuit. This significantly improves the battery's safety performance. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the insulating pad structure of this utility model; Figure 3 This is a schematic diagram of the top cover structure of this utility model; Figure 4 This is a schematic cross-sectional view of the top cover of this utility model; Figure 5 This is a cross-sectional view of the explosion-proof sheet of this utility model.

[0018] In the diagram: 1. Top cover; 11. Connecting terminal; 12. Conductive connector; 2. Explosion-proof sheet; 21. Explosion-proof hole; 22. Flanged edge; 3. Sealing assembly; 31. Sealing ring; 32. Sealing ring; 4. Positive electrode connecting piece; 5. Insulating pad; 51. Perforation; 52. Insulating coating; 61. Insulating isolation plate; 62. Buffer pad; 7. Protective cover; 71. Buckle; 8. Pressure relief channel; 81. High temperature resistant coating. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0020] Please see Figures 1 to 4 This utility model provides a technical solution: a high-safety cylindrical combination cap, including a top cover 1, an explosion-proof sheet 2, a sealing component 3, a positive electrode connecting piece 4, an insulating pad 5, and a device for preventing internal short circuits of the battery cell. The top cover 1 is located at the top, the explosion-proof sheet 2 is located below the top cover 1 and is fixedly connected to the top cover 1, the sealing component 3 is located below the explosion-proof sheet 2 and is tightly fitted with the outer shell of the cylindrical battery, the positive electrode connecting piece 4 passes through the top cover 1 and the explosion-proof sheet 2 and is connected to the positive electrode of the battery cell, and the insulating pad 5 is located between the positive electrode connecting piece 4 and the top cover 1 and the explosion-proof sheet 2. The sealing assembly 3 includes a sealing ring 31 and a sealing ring 32. The sealing ring 31 is made of rubber and is fitted onto the top edge of the cylindrical battery casing. The sealing ring 32 is positioned above the sealing ring 31 and is tightly fitted with the explosion-proof sheet 2. The sealing ring 32 is made of metal. The double sealing of the sealing ring 31 and the sealing ring 32 effectively improves the overall sealing reliability and reduces the risk of electrolyte leakage and external contamination. The explosion-proof sheet 2 has multiple explosion-proof holes 21, which are elliptical in shape. The edge of the explosion-proof hole 21 has a flange 22 that protrudes to one side. The flange 22 on the edge of the explosion-proof hole 21 protrudes to one side, which can guide the gas to be discharged in a specific direction. At the same time, the flange 22 structure enhances the strength of the edge of the explosion-proof hole 21, ensuring the stability and safety of the explosion-proof function. An insulating separator 61 is disposed between the battery cell and the positive electrode connecting piece 4, and a buffer pad 62 is disposed on the side of the insulating separator 61 close to the battery cell. The buffer pad 62 is made of rubber. The insulating separator 61 blocks the direct contact path between the two through physical isolation, and the rubber buffer pad 62 can absorb the vibration and impact during battery use. The double protection significantly reduces the risk of internal short circuit. The top cover 1 is equipped with a connection terminal 11 for connecting to an external circuit. The connection terminal 11 is connected to the positive electrode connection piece 4 through a conductive connector 12. The conductive connector 12 is made of copper. The connection terminal 11 provides a standardized interface for connecting to an external circuit, which simplifies the connection process between the battery and external devices. The copper conductive connector 12 connects the connection terminal 11 and the positive electrode connection piece 4, which can reduce resistance loss during current transmission. The insulating pad 5 has a through hole 51 that matches the positive electrode connecting piece 4. The inner wall of the through hole 51 is provided with an insulating coating 52, which is a polytetrafluoroethylene coating. The through hole 51 ensures that the positive electrode connecting piece 4 can pass through smoothly. The insulating pad 5 itself isolates the positive electrode connecting piece 4 from the top cover 1 and the explosion-proof piece 2. The polytetrafluoroethylene is used to further enhance the insulation effect and improve the electrical safety performance. The cylindrical combination cap also includes a protective cover 7 set on top of the top cover 1. The protective cover 7 is made of plastic and is detachably connected to the top cover 1 by a buckle 71. The plastic protective cover 7 covers the top cover 1 and can prevent external dust, water droplets and other contaminants from contacting the top cover 1 and the connecting terminal 11, thus playing a protective role. The detachable connection between the protective cover 7 and the top cover 1 by the buckle 71 facilitates quick disassembly and installation, making it convenient to inspect or replace the top cover 1 and related components, and extending the service life of the cap. An annular pressure relief channel 8 is provided between the top cover 1 and the explosion-proof plate 2. The pressure relief channel 8 is connected to the explosion-proof hole 21 on the explosion-proof plate 2. The inner wall of the pressure relief channel 8 is provided with a high-temperature resistant coating 81. The annular pressure relief channel 8 is connected to the explosion-proof hole 21 on the explosion-proof plate 2, providing a dedicated flow channel for the gas discharged from the explosion-proof hole 21, avoiding the accumulation of gas between the top cover 1 and the explosion-proof plate 2 and the generation of local high pressure. The high-temperature resistant coating 81 enhances the reliability of the explosion-proof system.

[0021] In this invention, the working steps of the device are as follows: First step: The sealing component 3 achieves efficient sealing through a double barrier plus elastic compensation mechanism. The rubber sealing ring 31 uses its own elasticity to tightly fit the top edge of the cylindrical battery shell. Its polymer chain structure can deform to fill the tiny gaps between the shell and the cap caused by processing errors, forming the first line of sealing defense to prevent moisture, impurities from entering and electrolyte from leaking out. The metal elastic sealing ring 32 is located above the sealing ring 31 and is tightly fitted with the explosion-proof sheet 2. When the battery is affected by temperature changes or external vibrations, the elastic deformation of the metal ring can compensate for the gap changes between the components in real time. The sealing pressure is strengthened by continuous pre-tightening force, forming a synergistic effect with the sealing ring 31, avoiding the sealing failure caused by aging or deformation of the traditional single sealing structure, and cutting off the internal and external material exchange channels from a physical level. The second step: The explosion-proof system achieves safe venting based on the principle of directional pressure relief and structural reinforcement. The circular or elliptical explosion-proof holes 21 on the explosion-proof sheet 2 are preset weak areas. When a large amount of gas is generated inside the battery due to abnormal conditions such as short circuit or overcharge, and the pressure rises to the threshold, the gas impact causes the material at the explosion-proof hole 21 to break first, forming an exhaust channel. The flange 22 at the edge of the hole changes the local stress distribution through the bending process. On the one hand, it guides the gas to be discharged in the specific direction pointed by the flange 22, avoiding the high-pressure airflow from directly impacting the top cover 1 or surrounding components and causing secondary damage. On the other hand, the flange 22 structure increases the thickness and rigidity of the material around the explosion-proof hole 21, so that the explosion-proof sheet 2 maintains structural stability under the pressure fluctuations of normal use. It will only trigger the breakage when the pressure exceeds the safety threshold, ensuring a precise response of not opening unless necessary and opening when necessary. The third step: Short circuit paths are blocked through a combination of physical isolation and buffering shock absorption. The insulating isolation plate 61 is made of a polymer material that is resistant to electrolyte corrosion. Its overall structure completely separates the battery cell and the positive electrode connecting piece 4 in space. By utilizing the high insulation resistance of the material itself, the conductive circuit formed by the direct contact between the two is cut off, thus avoiding the risk of short circuits caused by positive electrode tab misalignment or loose connecting piece. The buffer pad 62 made of sponge or rubber has a porous structure or high elastic modulus. When the battery is impacted or vibrated, the buffer pad 62 absorbs kinetic energy through its own compression deformation, reducing the relative displacement between the battery cell and the positive electrode connecting piece 4, reducing frictional loss on the surface of the insulating isolation plate 61, and preventing damage to the insulation layer caused by rigid collision, thus maintaining the long-term stability of the insulation performance of the insulating isolation plate 61.

[0022] It should be noted that the device structure and accompanying drawings of this utility model mainly describe the principle of this utility model. In terms of the technical aspects of this design principle, the setting of the power mechanism, power supply system and control system of the device is not fully described. However, under the premise that those skilled in the art understand the principle of the above utility model, the specific details of its power mechanism, power supply system and control system can be clearly understood. The control method in the application document is automatic control through a controller. The control circuit of the controller can be implemented by those skilled in the art through simple programming. All standard parts used can be purchased from the market, and can be customized according to the instructions and drawings. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the existing technology. The machinery, parts and equipment adopt conventional models in the existing technology, and the structure and principle of the components known to those skilled in the art can be known by those skilled in the art through technical manuals or conventional experimental methods.

[0023] It will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-safety cylindrical composite cap, characterized in that: The battery includes a top cover (1), an explosion-proof sheet (2), a sealing assembly (3), a positive electrode connecting piece (4), an insulating pad (5), and an insulating isolation plate (61) and a buffer pad (62) for preventing short circuits inside the battery cell. The top cover (1) is located at the top, the explosion-proof sheet (2) is located below the top cover (1) and is fixedly connected to the top cover (1), the sealing assembly (3) is located below the explosion-proof sheet (2) and fits tightly with the outer shell of the cylindrical battery, the positive electrode connecting piece (4) passes through the top cover (1) and the explosion-proof sheet (2) and is connected to the positive electrode of the battery cell, and the insulating pad (5) is located between the positive electrode connecting piece (4) and the top cover (1) and the explosion-proof sheet (2).

2. The high-safety cylindrical combination cap according to claim 1, characterized in that: The sealing assembly (3) includes a sealing ring (31) and a sealing ring (32). The sealing ring (31) is made of rubber and is fitted on the top edge of the cylindrical battery casing. The sealing ring (32) is positioned above the sealing ring (31) and is tightly fitted with the explosion-proof sheet (2). The sealing ring (32) is made of metal.

3. The high-safety cylindrical combination cap according to claim 1, characterized in that: The explosion-proof sheet (2) has multiple explosion-proof holes (21), which are elliptical in shape, and the edges of the explosion-proof holes (21) have flanges (22) that protrude to one side.

4. The high-safety cylindrical combination cap according to claim 1, characterized in that: The insulating isolation plate (61) is disposed between the battery cell and the positive electrode connecting piece (4), and the buffer pad (62) is disposed on the side of the insulating isolation plate (61) close to the battery cell. The material of the buffer pad (62) is rubber.

5. A high-safety cylindrical combination cap according to claim 1, characterized in that: The top cover (1) is equipped with a connection terminal (11) for connecting to an external circuit. The connection terminal (11) is connected to the positive electrode connection piece (4) through a conductive connector (12). The conductive connector (12) is made of copper.

6. A high-safety cylindrical combination cap according to claim 1, characterized in that: The insulating pad (5) has a perforation (51) adapted to the positive electrode connecting piece (4), and the inner wall of the perforation (51) is provided with an insulating coating (52), which is a polytetrafluoroethylene coating.

7. A high-safety cylindrical combination cap according to claim 1, characterized in that: The cylindrical combination cap also includes a protective cover (7) disposed above the top cover (1). The protective cover (7) is made of plastic and is detachably connected to the top cover (1) by a buckle (71).

8. A high-safety cylindrical combination cap according to claim 1, characterized in that: An annular pressure relief channel (8) is provided between the top cover (1) and the explosion-proof sheet (2). The pressure relief channel (8) is connected to the explosion-proof hole (21) on the explosion-proof sheet (2). The inner wall of the pressure relief channel (8) is provided with a high-temperature resistant coating (81).

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