Cylindrical waterproof lithium battery

Abstract

The utility model relates to lithium battery technical field especially is involved in a kind of columnar waterproof lithium battery, including columnar shell, lithium battery group, discharge circuit board and charging circuit board are integrally arranged in the inside of shell, lithium battery group is respectively connected with discharge circuit board and charging circuit board electricity, shell has insertion end and exposed end, discharge circuit board is provided with the discharge connecting terminal that protrudes in insertion end, and waterproof rubber pad is set on insertion end and is enclosed in discharge connecting terminal;Columnar waterproof lithium battery is integrated by waterproof design and function in multiple positions, lithium battery group, discharge circuit board and charging circuit board are ingeniously integrated in columnar shell, waterproof rubber pad is used in insertion end and is enclosed discharge connecting terminal, and moisture intrusion discharge connection area is blocked;Exposed end is provided with first waterproof rubber ring to strengthen side sealing, cooperate with the anti short circuit circuit of charging connecting terminal, both prevent external moisture from entering, also avoid short circuit risk when charging.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, and in particular to a cylindrical waterproof lithium battery. Background Technology

[0002] With the continuous development of new energy technologies, lithium batteries are widely used in various outdoor electrical equipment, such as electric vehicles and outdoor energy storage power supplies, due to their advantages such as high energy density and long cycle life. However, lithium batteries inevitably experience capacity decay and performance degradation during long-term use. When the battery performance degrades to a certain level, it not only fails to meet the normal operation requirements of the equipment, but also increases safety risks such as overcharging and over-discharging. Therefore, timely replacement is usually necessary.

[0003] Currently, some outdoor electrical devices use a power supply method that combines a cylindrical battery compartment with a compatible lithium battery module. Users can quickly power the device by inserting the lithium battery module into the battery compartment. This design facilitates individual battery replacement and maintenance, effectively improving the ease of use of the device. However, in special scenarios such as outdoors, the battery connection parts of the device are highly susceptible to damage from rain, humid air, and other factors. If the waterproof performance of the battery connection parts is inadequate, water entering the device may lead to serious consequences such as short circuits and leakage, damaging the device and threatening the user's personal safety.

[0004] While existing technologies have some research and application regarding waterproofing of battery connection parts, the design of waterproofing connections between cylindrical battery compartments and lithium battery modules still suffers from problems such as poor waterproofing performance, complex structures leading to assembly difficulties, and high costs. These limitations make it difficult to fully meet the waterproof, safe, and reliable requirements of outdoor electrical equipment for battery connection parts. Therefore, there is an urgent need for a technical solution that can effectively improve the waterproofing performance of battery connection parts while also ensuring structural simplicity, ease of assembly, and cost control. Utility Model Content

[0005] To overcome the shortcomings mentioned above, this utility model aims to provide a technical solution that can solve the above problems.

[0006] A cylindrical waterproof lithium battery includes a cylindrical shell, and a lithium battery pack, a discharge circuit board and a charging circuit board are integrated inside the shell. The lithium battery pack is electrically connected to the discharge circuit board and the charging circuit board respectively. The shell has an insertion end and an exposed end. The discharge circuit board is provided with a discharge connection terminal that protrudes from the insertion end, and a waterproof gasket surrounding the discharge connection terminal is provided on the insertion end.

[0007] The charging circuit board is provided with a charging connection terminal that protrudes from the exposed end. The charging circuit board is also provided with a short-circuit protection circuit that acts on the charging connection terminal. A first waterproof rubber ring is provided on the side of the exposed end, and a connecting part is also formed on the side of the exposed end. A fixing hole is provided on the connecting part, and a screw assembly is provided in the fixing hole. A second waterproof rubber ring is fitted on the screw assembly to seal between the screw assembly and the fixing hole.

[0008] Preferably, the outer shell includes a base, a first side shell, and a second side shell that fit together. An ultrasonic welding structure is provided on the mating surfaces of the base, the first side shell, and the second side shell. The base, the first side shell, and the second side shell are sealed together by the ultrasonic welding structure. The lower ends of the first side shell and the second side shell have protrusions formed along their sides. The base fits onto the lower ends of the first side shell and the second side shell and is adapted to the protrusions, so that the base and the protrusions form a connection after the shell is closed. The insertion end is located at the upper end of the first side shell and the second side shell, and the exposed end is located on the base.

[0009] Preferably, the ultrasonic welding structure includes a first ultrasonic welding groove formed on the side cover surface of the first side shell, a first ultrasonic welding edge formed on the side cover surface of the second side shell, a second ultrasonic welding groove formed on the base cover surface, and a second ultrasonic welding edge formed on the end cover surfaces of the first and second side shells. The first ultrasonic welding edge and the first ultrasonic welding groove are ultrasonically welded, and the second ultrasonic welding edge and the second ultrasonic welding groove are ultrasonically welded. The first ultrasonic welding groove and the second ultrasonic welding edge are connected to form an enclosing structure.

[0010] Preferably, the fixing hole includes a first hole body disposed at the lower end of the first side shell or the second side shell, and the fixing hole also includes a second hole body disposed on the base and mating with the first hole body. A third waterproof rubber ring is disposed between the mating surfaces of the first hole body and the second hole body. A blocking ring is also formed inward at the mating position of the first hole body and the second hole body. The screw assembly abuts against the blocking ring. The second waterproof rubber ring is disposed between the blocking ring and the screw assembly.

[0011] Preferably, the screw assembly includes a tightening head, a connecting rod formed on the tightening head, a threaded connecting section formed on the end of the connecting rod, and a washer sleeved on the connecting rod. The tightening head is confined in the second hole by a retaining ring. The connecting rod passes through the retaining ring, so that the threaded connecting section is in the first hole and can be exposed outside the connecting part along the first hole. The washer is disposed between the tightening head and the retaining ring, and the washer is used to press the second waterproof rubber ring to seal between the connecting rod and the retaining ring.

[0012] Preferably, the screw assembly further includes an open washer and a spring sleeved on the connecting rod, the open washer being disposed between the retaining ring and the threaded connection section, and the spring being disposed between the tightening head and the washer.

[0013] Preferably, the waterproof gasket has a normal-shaped boss on its inner perimeter.

[0014] Compared with the prior art, the beneficial effects of this utility model are:

[0015] The cylindrical waterproof lithium battery cleverly integrates the lithium battery pack, discharge circuit board, and charging circuit board into a cylindrical shell through multi-part waterproof design and functional integration. At the insertion end, a waterproof gasket surrounds the discharge connection terminal to prevent moisture from entering the discharge connection area. The exposed end is equipped with a first waterproof gasket to enhance the side seal, which, together with the short-circuit protection circuit of the charging connection terminal, prevents external moisture from entering and avoids the risk of short circuit during charging. The screw assembly, together with a second waterproof gasket, ensures a secure connection while achieving a seal. The synergistic effect of multiple waterproof structures significantly improves the battery's waterproof performance and safety in outdoor environments, while its compact structure facilitates installation and fixation.

[0016] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of this utility model;

[0019] Figure 2 This is a schematic diagram of the transverse cross-section structure of this utility model, with a magnified view of a portion thereof;

[0020] Figure 3 This is a schematic diagram of the longitudinal cross-sectional structure of this utility model;

[0021] Figure 4 This is a utility model Figure 3 Schematic diagram of the structure at point A;

[0022] Figure 5 This is a utility model Figure 3 Schematic diagram of the structure at point B;

[0023] Figure 6 This is a circuit diagram of a short-circuit protection circuit according to this utility model.

[0024] The reference numerals and names in the figure are as follows:

[0025] 10. Outer shell, 11. Base, 12. First side shell, 13. Second side shell, 14. First ultrasonic welding groove, 15. First ultrasonic welding edge, 16. Second ultrasonic welding groove, 17. Second ultrasonic welding edge, 20. Lithium battery pack, 30. Discharge circuit board, 31. Discharge connection terminal, 32. Waterproof rubber pad, 321. Boss, 40. Charging circuit board, 41. Charging connection terminal, 43. First waterproof rubber ring, 50. Connecting part, 51. Fixing hole, 51. First hole body, 511. Second hole body, 512. Third waterproof rubber ring, 513. Blocking ring, 514. Screw assembly, 60. Second waterproof rubber ring, 61. Tightening head, 62. Connecting rod, 63. Threaded connection section, 64. Washer, 65. Open washer, 66. Spring, 67. Detailed Implementation

[0026] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, and 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.

[0027] Please see Figure 1-6 In this embodiment of the utility model, a cylindrical waterproof lithium battery includes a cylindrical outer shell 10. Inside the outer shell 10, a lithium battery pack 20, a discharge circuit board 30, and a charging circuit board 40 are integrated. The lithium battery pack 20 is electrically connected to the discharge circuit board 30 and the charging circuit board 40 respectively. The outer shell 10 has an insertion end and an exposed end. The discharge circuit board 30 is provided with a discharge connection terminal 31 that protrudes from the insertion end, and a waterproof pad 32 surrounding the discharge connection terminal 31 is provided on the insertion end.

[0028] The charging circuit board 40 is provided with a charging connection terminal 41 exposed at its external end. The charging circuit board 40 is also provided with a short-circuit protection circuit that acts on the charging connection terminal 41. A first waterproof rubber ring 43 is provided on the side of the exposed end, and a connecting part 50 is also formed on the side of the exposed end. A fixing hole 51 is provided on the connecting part 50. A screw assembly 60 is provided in the fixing hole 51. A second waterproof rubber ring 61 is fitted on the screw assembly 60 to seal between the screw assembly 60 and the fixing hole 51.

[0029] like Figure 6As shown, the JW7260TSOTB#TRPBF chip is connected to an external MOSFET in the short-circuit protection circuit of this technical solution. The JW7260TSOTB#TRPBF is a positive voltage ideal diode controller. Its main function is to drive an external N-channel MOSFET, allowing the N-channel MOSFET to function like a diode, while avoiding the high conduction loss problem of traditional Schottky diodes. In the short-circuit protection circuit, this chip works in conjunction with the external MOSFET to quickly detect short-circuit conditions and promptly cut off the circuit, thereby ensuring the safety of the system. Its working principle is as follows:

[0030] When the circuit is operating normally, the JW7260TSOTB#TRPBF chip outputs a suitable drive signal to the gate (G) of the external N-channel MOSFET. This drive signal turns the MOSFET on, at which point the resistance between the source (S) and drain (D) of the MOSFET becomes very small, allowing current to flow smoothly from the power supply to the load. If a short circuit occurs at the load, the current will increase sharply; the JW7260TSOTB#TRPBF chip can sensitively detect this abnormal current change because it has internal detection circuitry that monitors the voltage difference or current magnitude between the source and drain of the MOSFET in real time. In actual circuit design, appropriate capacitors, resistors, and other components need to be added according to the specific application scenario to optimize circuit performance and stability; simultaneously, the model and parameters of the external MOSFET should be selected appropriately based on the power and current requirements of the load.

[0031] A protruding connecting portion 50 is formed on the exposed side of the battery compartment. The connecting portion 50 is used to set the fixing hole 51 and the screw assembly 60, facilitating the insertion and fixing of the cylindrical waterproof lithium battery into the battery compartment. Specifically, by providing a structure that adapts to the connecting portion 50 at the opening of the battery compartment, the cylindrical waterproof lithium battery is inserted, and the connecting portion 50 fits tightly into the opening of the battery compartment. Then, the screw assembly 60 is used to fix it to the opening of the battery compartment, completing the assembly of the cylindrical waterproof lithium battery. Based on this structure, the cylindrical waterproof lithium battery cleverly integrates multiple waterproof design elements and functions, integrating the lithium battery pack 20 and the... The circuit board 30 and the charging circuit board 40 are integrated into the cylindrical housing 10. At the insertion end, the discharge connection terminal 31 is surrounded by a waterproof gasket 32 ​​to prevent moisture from entering the discharge connection area. The exposed end is provided with a first waterproof gasket 43 to strengthen the side seal. Together with the short-circuit protection circuit of the charging connection terminal 41, it not only prevents external moisture from entering, but also avoids the risk of short circuit during charging. The screw assembly 60, together with the second waterproof gasket 61, ensures a fixed connection and achieves a seal. The multiple waterproof structures work together to significantly improve the waterproof performance and safety of the battery in outdoor environments. At the same time, the structure is compact and easy to install and fix.

[0032] Please see Figure 1 Based on the above technical solution, the outer shell 10 is further proposed to include a base 11, a first side shell 12, and a second side shell 13 that overlap each other. An ultrasonic welding structure is provided on the overlapping surfaces of the base 11, the first side shell 12, and the second side shell 13. The base 11, the first side shell 12, and the second side shell 13 are sealed together by the ultrasonic welding structure. The lower ends of the first side shell 12 and the second side shell 13 are formed with protrusions along the sides. The base 11 covers the lower ends of the first side shell 12 and the second side shell 13 and is adapted to the protrusions, so that the base 11 and the protrusions form a connecting part 50 after the covering is completed. The insertion end is located at the upper end of the first side shell 12 and the second side shell 13, and the exposed end is located on the base 11. The shell 10 structure design, through an innovative split construction and connection method, further enhances the overall performance of the cylindrical waterproof lithium battery. By adopting a split design of the base 11, the first side shell 12, and the second side shell 13, combined with an ultrasonic welding structure, a tighter and more reliable sealing effect can be achieved compared to traditional snap-fit ​​or screw connections, effectively preventing moisture from seeping in from the seams of the shell 10 and enhancing the battery's waterproof performance. At the same time, the ultrasonic welding process reduces the use of connectors, simplifies the assembly process, improves production efficiency, and reduces production costs. The protrusions at the lower ends of the first side shell 12 and the second side shell 13 are adapted to the base 11 to form the connecting part 50. This structural design not only makes full use of the space of the shell 10, making the connecting part 50 integrally formed with the shell 10 and enhancing structural strength, but also further simplifies the overall structure, facilitating mold design and manufacturing.

[0033] Please see Figure 2 and Figure 4 Based on the above technical solution, a further proposed ultrasonic welding structure includes a first ultrasonic welding groove 14 formed on the side cover surface of the first side shell 12, a first ultrasonic welding edge 15 formed on the side cover surface of the second side shell 13, a second ultrasonic welding groove 16 formed on the cover surface of the base 11, and a second ultrasonic welding edge 17 formed on the end cover surfaces of the first side shell 12 and the second side shell 13. The first ultrasonic welding edge 15 and the first ultrasonic welding groove 14 are ultrasonically welded, and the second ultrasonic welding edge 17 and the second ultrasonic welding groove 16 are ultrasonically welded. The first ultrasonic welding groove 14 and the second ultrasonic welding edge 17 are connected to form an enclosing structure. This standardized welding structure design facilitates mold development and mass production, reduces manufacturing process difficulty and assembly errors, improves product quality consistency, and also helps control production costs and improve production efficiency.

[0034] Please see Figure 5Based on the above technical solution, it is further proposed that the fixing hole 51 includes a first hole body 511 disposed at the lower end of the first side shell 12 or the second side shell 13, and the fixing hole 51 also includes a second hole body 512 disposed on the base 11 and mating with the first hole body 511. A third waterproof rubber ring 513 is disposed between the mating surfaces of the first hole body 511 and the second hole body 512. A retaining ring 514 is also formed inward at the mating position of the first hole body 511 and the second hole body 512. The screw assembly 60 abuts against the retaining ring 514. The second waterproof rubber ring 61 is disposed at the lower end of the first side shell 12 or the second side shell 13. Between the retaining ring 514 and the screw assembly 60, a third waterproof rubber ring 513 is added at the joint between the first hole 511 and the second hole 512, forming a multi-level sealing structure with the retaining ring 514 and the second waterproof rubber ring 61. This effectively prevents moisture from penetrating along the screw hole, further improving the battery's waterproof performance. The design of the tightening head 62 in the screw assembly 60, in conjunction with the retaining ring 514, not only ensures the precise positioning of the screw installation but also prevents the screw from being over-screwed and damaging the internal structure through the limiting of the tightening head 62, thus enhancing the reliability and safety of the installation.

[0035] The screw assembly 60 includes a tightening head 62, a connecting rod 63 formed on the tightening head 62, a threaded connecting section 64 formed on the end of the connecting rod 63, and a washer 65 sleeved on the connecting rod 63. The tightening head 62 is confined in the second hole 512 by a retaining ring 514. The connecting rod 63 passes through the retaining ring 514, so that the threaded connecting section 64 is located in the first hole 511 and can protrude beyond the connecting portion 50 along the first hole 511. The washer 65 is disposed between the tightening head 62 and the retaining ring 514, and the washer 65 is used to press the second waterproof rubber ring 61 to seal between the connecting rod 63 and the retaining ring 514. The squeezing action of the washer 65 on the second waterproof rubber ring 61 makes the waterproof rubber ring tightly fit the gap between the connecting rod 63 and the retaining ring 514, forming a dynamic seal, which maintains a good waterproof effect even in a vibration environment.

[0036] The screw assembly 60 also includes an open washer 66 and a spring 67 sleeved on the connecting rod 63. The open washer 66 is located between the retaining ring 514 and the threaded connection section 64, and the spring 67 is located between the tightening head 62 and the washer 65. The open washer 66 enhances the tightening effect of the threaded connection section 64 and prevents the screw from loosening, while the elastic preload provided by the spring 67 can compensate for component displacement caused by factors such as vibration and temperature changes, ensuring the long-term effectiveness of the sealing structure.

[0037] Please see Figure 1 and Figure 3Based on the above technical solution, a further proposed feature is an inner perimeter normal-formed boss 321 for the waterproof gasket 32. The boss 321 allows for a tighter compression contact with the battery compartment interface when the lithium battery module is inserted into the battery compartment. Compared to the flat waterproof gasket 32, the boss 321 increases the contact area and sealing pressure, effectively filling connection gaps and further blocking the path of moisture intrusion into the discharge connection terminal 31. Furthermore, a potting encapsulation is provided inside the outer casing 10 at the location corresponding to the discharge circuit board 30. The potting compound tightly wraps the discharge circuit board 30 and its connecting lines, filling the gap between the circuit board and the outer casing 10, forming a dense protective layer. This effectively prevents external impurities such as moisture, dust, and humidity from intruding into the circuit board, further enhancing the battery's waterproof and dustproof performance.

[0038] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention.

Claims

1. A cylindrical waterproof lithium battery, characterized in that, The device includes a cylindrical outer shell (10), and a lithium battery pack (20), a discharge circuit board (30) and a charging circuit board (40) are integrated inside the outer shell (10). The lithium battery pack (20) is electrically connected to the discharge circuit board (30) and the charging circuit board (40) respectively. The outer shell (10) has an insertion end and an exposed end. The discharge circuit board (30) is provided with a discharge connection terminal (31) that protrudes from the insertion end, and a waterproof gasket (32) that surrounds the discharge connection terminal (31) is provided on the insertion end. The charging circuit board (40) is provided with a charging connection terminal (41) that protrudes from the exposed end. The charging circuit board (40) is also provided with a short-circuit protection circuit that acts on the charging connection terminal (41). A first waterproof rubber ring (43) is provided on the side of the exposed end, and a connecting part (50) is also formed on the side of the exposed end. A fixing hole (51) is provided on the connecting part (50), and a screw assembly (60) is provided in the fixing hole (51). A second waterproof rubber ring (61) is provided on the screw assembly (60) to seal between the screw assembly (60) and the fixing hole (51).

2. The cylindrical waterproof lithium battery according to claim 1, characterized in that, The outer shell (10) includes a base (11), a first side shell (12), and a second side shell (13) that fit together. An ultrasonic welding structure is provided on the mating surfaces of the base (11), the first side shell (12), and the second side shell (13). The base (11), the first side shell (12), and the second side shell (13) are sealed together by the ultrasonic welding structure. The lower ends of the first side shell (12) and the second side shell (13) are formed with protrusions along the sides. The base (11) fits onto the lower ends of the first side shell (12) and the second side shell (13) and is adapted to the protrusions, so that the base (11) and the protrusions form a connection (50) after the mating. The insertion end is located at the upper end of the first side shell (12) and the second side shell (13), and the exposed end is located on the base (11).

3. A cylindrical waterproof lithium battery according to claim 2, characterized in that, The ultrasonic welding structure includes a first ultrasonic welding groove (14) formed on the side cover surface of the first side shell (12), a first ultrasonic welding edge (15) formed on the side cover surface of the second side shell (13), a second ultrasonic welding groove (16) formed on the cover surface of the base (11), and a second ultrasonic welding edge (17) formed on the end cover surfaces of the first side shell (12) and the second side shell (13). The first ultrasonic welding edge (15) and the first ultrasonic welding groove (14) are ultrasonically welded, and the second ultrasonic welding edge (17) and the second ultrasonic welding groove (16) are ultrasonically welded. The first ultrasonic welding groove (14) and the second ultrasonic welding edge (17) are connected to form an enclosing structure.

4. A cylindrical waterproof lithium battery according to claim 2, characterized in that, The fixing hole (51) includes a first hole body (511) disposed at the lower end of the first side shell (12) or the second side shell (13). The fixing hole (51) also includes a second hole body (512) disposed on the base (11) and mating with the first hole body (511). A third waterproof rubber ring (513) is disposed between the mating surfaces of the first hole body (511) and the second hole body (512). A blocking ring (514) is also formed inward at the mating position of the first hole body (511) and the second hole body (512). The screw assembly (60) abuts against the blocking ring (514). The second waterproof rubber ring (61) is disposed between the blocking ring (514) and the screw assembly (60).

5. A cylindrical waterproof lithium battery according to claim 4, characterized in that, The screw assembly (60) includes a tightening head (62), a connecting rod (63) formed on the tightening head (62), a threaded connecting section (64) formed on the end of the connecting rod (63), and a washer (65) sleeved on the connecting rod (63). The tightening head (62) is restricted in the second hole (512) by a retaining ring (514). The connecting rod (63) passes through the retaining ring (514) so ​​that the threaded connecting section (64) is in the first hole (511) and can be exposed outside the connecting part (50) along the first hole (511). The washer (65) is disposed between the tightening head (62) and the retaining ring (514), and the washer (65) is used to press the second waterproof rubber ring (61) to seal between the connecting rod (63) and the retaining ring (514).

6. A cylindrical waterproof lithium battery according to claim 5, characterized in that, The screw assembly (60) also includes an open washer (66) and a spring (67) sleeved on the connecting rod (63), the open washer (66) being disposed between the retaining ring (514) and the threaded connection section (64), and the spring (67) being disposed between the tightening head (62) and the washer (65).

7. A cylindrical waterproof lithium battery according to claim 1, characterized in that, The inner circumferential normal forming boss (321) of the waterproof rubber pad (32).

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