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CN-120862055-B - Welding detection method for lithium ion battery sealing nails

CN120862055BCN 120862055 BCN120862055 BCN 120862055BCN-120862055-B

Abstract

The invention relates to a welding detection method of a lithium ion battery sealing nail, which comprises the following steps of S1, assembling the sealing nail and a glue nail, then assembling the sealing nail and a battery cover plate liquid injection port, S2, comparing and judging the nail placing track of the sealing nail through a CCD system, calculating the obtained data result of a photo through calculation software in the system to obtain a welding track, transmitting a welding track instruction to laser welding equipment, S3, pre-spot welding and full-welding the sealing nail through the laser welding equipment, S4, performing a pressing test on the sealing nail, S5, performing quality side leakage detection on a battery of the welding sealing nail through a helium system, pushing the sealing nail into a containing cavity after the sealing nail is adsorbed by an adsorption component, driving a sealing nail to drop through a cutter, dispensing the sealing nail through a glue dispenser, cutting the glue nail, and bonding the sealing nail at the same time, and improving the working efficiency.

Inventors

  • CHANG FUCHENG
  • FAN LIJIAN
  • LI MINGXING
  • ZHANG ZHAOQIANG
  • HOU XUERU
  • Jin Hougui

Assignees

  • 浙江天能新能源有限公司

Dates

Publication Date
20260508
Application Date
20250611

Claims (9)

  1. 1. A welding detection method of a lithium ion battery sealing nail comprises the following steps: S1, assembling a sealing nail (1) and a glue nail (2) and then assembling the sealing nail and a battery cover plate liquid injection port; S2, comparing and judging the nail placing track of the sealing nail (1) through a CCD system, calculating the data result of the obtained photo through calculation software in the system to obtain a welding track, and transmitting a welding track instruction to laser welding equipment; S3, performing pre-spot welding and full-length welding on the sealing nail (1) through laser welding equipment; S4, performing a pressing test on the sealing nail (1); s5, detecting quality side leakage of the battery welded with the sealing nail (1) through a helium system; Wherein, in the step S1, the sealing nail (1) and the glue nail (2) are assembled through an assembling device, the assembling device comprises a base (4), a glue dispenser (5) arranged on one side of the base (4) and a transmission track (6) arranged on one side of the base (4) and used for transmitting the sealing nail (1), an adsorption component (7) is arranged on one side of the transmission track (6), a driving component (8) and a cutting component (9) driven by the driving component (8) are arranged on the base (4), the cutting component (9) comprises a cutting knife (91) and a containing cavity (92) arranged on the cutting knife (91), a sliding component (10) is arranged on the moving path of the cutting knife (91), a bearing component (11) and a pushing component (12) are arranged on the base (4), the bearing component (11) comprises a bearing seat (111) used for bearing the glue nail (2), the adsorption component (7) is used for pushing the sealing nail (1) into the containing cavity (92) after being adsorbed, the glue dispenser (5) is used for driving the sealing nail (1) to drop down, the sliding component (10) is used for driving the glue nail (2) to one side of the accommodating cavity (92) when the glue nail (2) is cut by the cutting knife (91), and the pushing component (12) is used for pushing the sealing nail (1) to be bonded with the glue nail (2).
  2. 2. The welding detection method of the sealing nail for the lithium ion battery according to claim 1, wherein the adsorption assembly (7) comprises a bottom plate (71) fixedly arranged on the transmission track (6), a sliding seat (72) fixedly arranged on the bottom plate (71), a cylinder body (73) fixedly arranged on the sliding seat (72), a sucker (74) fixedly arranged on the cylinder body (73), a piston (75) slidingly arranged in the cylinder body (73), a piston rod (76) fixedly arranged on the piston (75), a first limit rod (77) slidingly arranged in the cylinder body (73), an air hole (78) formed on the cylinder body (73), a stop rod (79) fixedly arranged on the sliding seat (72), a channel (710) fixedly arranged on the transmission track (6), a fixed rod (711) fixedly arranged on the channel (710) and a limit post (712), a second limit rod (713) slidingly arranged on the fixed rod (711), a sliding plate (714) slidingly arranged on the bottom plate (71), the piston rod (76) is fixedly connected with the sliding plate (75), and the piston rod (76) is fixedly connected with the sliding plate (77) and is provided with two sides of the first limit rod (77) which are matched with the first limit rod (73), springs are arranged between the second limiting rods (713) and the channels (710), the second limiting rods (713) are matched with the sealing nails (1), and the diameters of the channels (710) are the same as the diameters of the sealing nails (1).
  3. 3. The welding detection method of the lithium ion battery sealing nail is characterized in that the driving assembly (8) comprises a supporting frame (81) fixedly arranged on the base (4), a motor (82) fixedly arranged on the supporting frame (81), a first screw rod (83) rotatably arranged on the supporting frame (81) and a guide rod (84) fixedly arranged on the supporting frame (81), and the first screw rod (83) is fixedly connected with an output shaft of the motor (82).
  4. 4. The welding detection method of the lithium ion battery sealing nail according to claim 3, wherein the cutting assembly (9) further comprises a sliding plate (93) arranged on the first screw rod (83) in a sliding mode and a plurality of third limiting rods (94) arranged on the accommodating cavity (92) in a sliding mode, the cutting knife (91) is fixedly connected with the sliding plate (93), the sliding plate (93) is matched with the guide rod (84), a spring is arranged between the third limiting rods (94) and the accommodating cavity (92), the third limiting rods (94) are matched with the sealing nail (1), and the diameter of the accommodating cavity (92) is identical with that of the channel (710).
  5. 5. The welding detection method of the lithium ion battery sealing nail is characterized in that the sliding assembly (10) comprises a sliding groove (101) formed in a base (4), a second screw rod (102) rotatably arranged in the sliding groove (101), a rotating shaft (103) rotatably arranged on the base (4), a gear (104) fixedly arranged on the rotating shaft (103) and a rack (105) fixedly arranged on a sliding plate (93), the gear (104) is meshed with the rack (105), belt pulleys are arranged on the second screw rod (102) and the rotating shaft (103), and a belt is arranged between the belt pulleys.
  6. 6. The welding detection method of the lithium ion battery sealing nail according to claim 5, wherein the bearing assembly (11) further comprises a first sliding block (112) and a second sliding block (113) which are arranged in the sliding groove (101) in a sliding mode, a U-shaped seat (114) fixedly arranged on the first sliding block (112) and a baffle plate (115) fixedly arranged on the bearing seat (111), the second sliding block (113) is fixedly connected with the bearing seat (111), and the U-shaped seat (114) and the bearing seat (111) are matched with the glue nail (2).
  7. 7. The welding detection method of the lithium ion battery sealing nail, as set forth in claim 3, wherein the pushing component (12) comprises a ring sleeve (121) arranged on the base (4) in a sliding manner, a push rod (122) fixedly arranged on the ring sleeve (121) and a cylinder (123) fixedly arranged on the support frame (81), an output shaft of the cylinder (123) is fixedly connected with the ring sleeve (121), and the push rod (122) is matched with the sealing nail (1).
  8. 8. The welding detection method of the lithium ion battery sealing nail of claim 7, wherein a rubber layer is arranged on the push rod (122).
  9. 9. The welding detection method of the lithium ion battery sealing nail of claim 6, wherein anti-skidding lines are arranged on the U-shaped seat (114) and the bearing seat (111).

Description

Welding detection method for lithium ion battery sealing nails Technical Field The invention relates to the technical field of energy storage battery equipment, in particular to a welding detection method of a lithium ion battery sealing nail. Background The lithium battery is a power supply for providing a power source for a power tool, and has the advantages of long service life, practicability, safety, large capacity, small volume, light weight and the like, and is widely applied to a plurality of fields. Lithium ion batteries are widely used in our lives as one of new energy sources, and aluminum-shell batteries are one of the most widely used battery models in lithium ion batteries because of their safety advantages. In the lithium battery production process, the sealing nail welding is an important part component of the battery cell, and is the last laser welding process in the lithium battery cell production, so that the rate of the process is critical, and the cost loss of the product scrapped to the final stage is large for battery manufacturers. At present, most battery manufacturers in the sealing nail welding process in the new energy industry select YAG pulse welding equipment, and the YAG laser has excellent single pulse energy stability because of being provided with an arbitrary waveform real-time energy negative feedback technology, so that the primary welding rate of more than or equal to 99.5% can be finally realized. However, the YAG laser is not perfect, because the YAG laser has an upper limit on power, the current maximum power in the market is 600W, and because the power is limited, the welding frequency is limited, so that only a pulse welding mode with a collimator head emitting light can be adopted at present. Chinese patent publication No. CN115846920B discloses a welding method of a battery sealing nail, which includes inserting the sealing nail into a liquid injection hole of a battery end cap, wherein the battery end cap has a region to be heated surrounding the periphery of the sealing nail, disposing a heating device in the region to be heated, activating the heating device to heat the region to be heated, and activating the welding device to weld the sealing nail, wherein the temperature of a welding position of the sealing nail is greater than the temperature of the region to be heated. The welding method of the battery sealing nail provided by the embodiment of the application can solve the problem that the welding position of the sealing nail is cracked due to too fast cooling after welding, so as to ensure the sealing effect of the sealing nail and reduce the leakage rate of the battery. However, the inventor finds that in the actual production process, the maximum penetration depth of the sealing nails is 0.3 mm-0.7 mm, gaps exist between the sealing nails and the cover plate in the process of forming the molten pool, the gaps between each group of sealing nails and the cover plate are different, the stress born by the molten pool with low penetration depth when the sealing nails are solidified facing different gaps is different, and under most conditions, the low penetration depth molten pool can generate cracks on a wide gap, the too low penetration depth not only affects the welding strength, but also can improve the occurrence probability of cracks at the welding seam, the crack defect seriously affects the performance of the battery core, even threatens the safety of the battery core, and therefore, the welding quality of the sealing nails in the lithium ion power battery is required to be improved, and meanwhile, the safety performance of the battery core is required to be fully inspected under a 30-fold magnifying glass. Disclosure of Invention The invention aims at overcoming the defects of the prior art, and provides a welding detection method for a lithium ion battery sealing nail, which is characterized in that the sealing nail is assembled with a glue nail and then inserted into a battery cover plate liquid injection port, the nail placing track of the sealing nail is compared and judged through a CCD system, the obtained data result of a photo is calculated by calculation software in the system to obtain a welding track, a welding track instruction is transmitted to laser welding equipment, the laser welding equipment performs pre-spot welding and full-spot welding on the sealing nail, the pressing test is performed on the sealing nail, the quality side leakage detection is performed on a battery for welding the sealing nail through a helium system, and the CCD system and the welding process cooperate, so that the welding method has good welding effect, reduces the quantity and labor intensity of appearance inspection manpower, saves the cost and achieves the aims of reducing personnel and improving efficiency. The technical solution of the invention is as follows: A welding detection method of a lithium ion battery sealing nail comprises the following ste