Battery liquid injection hole sealing laser welding device

Abstract

The application provides a battery liquid injection hole sealing laser welding device, which comprises a mounting seat, a laser processing assembly, a wire feeding assembly, a coaxial nozzle assembly and a welding protection air outlet device; the laser processing assembly and the wire feeding assembly are respectively installed at two ends of the mounting seat, the coaxial nozzle assembly is installed at a laser output end of the laser processing assembly, the wire feeding assembly is communicated with the coaxial nozzle assembly, the welding protection air outlet device is installed on the laser processing assembly, and an air outlet of the welding protection air outlet device is arranged close to a welding port of the coaxial nozzle assembly. The battery liquid injection hole sealing laser welding device provided by the application solves the problems of virtual welding, pinhole, crack and weld burst point which are caused by laser direct lithium battery liquid injection welding sealing through the process of melting a welding wire by laser radiation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery welding, in particular to a battery liquid injection hole sealing laser welding device. BACKGROUND

[0002] Power batteries have become one of the green energy sources with promising development in the new energy industry due to their advantages of strong power storage capacity, recyclability, long service life, and more environmental protection than ordinary nickel-chromium batteries.

[0003] According to the current production process of the battery, the liquid injection hole of the top cover has a containing groove, so that there will be residual electrolyte and its crystals in the containing groove during the injection and transportation of the battery electrolyte. In the subsequent battery liquid injection hole sealing welding process, the conventional method in the industry is to use laser to directly weld, but laser welding is a non-contact welding method, so the cleanliness of the battery surface is required to be high, otherwise it is easy to produce virtual welding, pinholes, cracks and weld seam burst points, thereby affecting the service life of the product. SUMMARY

[0004] In view of the defects in the prior art, the purpose of the present application is to provide a battery liquid injection hole sealing laser welding device.

[0005] The battery liquid injection hole sealing laser welding device provided by the present application comprises a mounting seat, a laser processing assembly, a wire feeding assembly, a coaxial nozzle assembly and a welding protection gas outlet device. The laser processing assembly and the wire feeding assembly are respectively installed at both ends of the mounting seat. The coaxial nozzle assembly is installed at the laser output end of the laser processing assembly. The wire feeding assembly is in communication with the coaxial nozzle assembly, and part of the welding wire in the wire feeding assembly enters the coaxial nozzle assembly. The welding protection gas outlet device is installed on the laser processing assembly, and the gas outlet of the welding protection gas outlet device is arranged close to the welding port of the coaxial nozzle assembly.

[0006] Preferably, the laser processing assembly comprises a laser optical fiber, a laser processing head and a laser emitting head coaxially arranged along a first direction. The laser optical fiber is installed at the top incident port of the laser processing head. The bottom of the laser processing head is connected with the laser emitting head. The laser emitting head is connected with the laser input end of the coaxial nozzle assembly. The laser processing head is connected with the mounting seat.

[0007] Preferably, the wire feeding assembly comprises a wire feeding motor, a wire feeding roller and a wire feeding pipe. The wire feeding motor drives the wire feeding roller to rotate. One end of the wire feeding pipe is in communication with the coaxial nozzle assembly. The welding wire on the coiled wire is wound on the wire feeding roller and passes through the discharge port of the wire feeding roller to enter the coaxial nozzle assembly through the wire feeding pipe.

[0008] Preferably, the wire feeding assembly further comprises a sealed box, the wire feeding motor, the wire feeding roller and the welding wire are arranged in the sealed box, one end of the wire feeding pipe is communicated with the discharge port of the wire feeding roller through the sealed box.

[0009] Preferably, the coaxial nozzle assembly comprises a nozzle connecting block and a coaxial nozzle, the nozzle connecting block is connected with the laser processing assembly at the top in the first direction to receive the laser beam emitted by the laser processing assembly; the coaxial nozzle is provided with a molten pool protection gas inlet pipeline, a flux feeding pipeline, a welding wire molten pool and a molten pool isolation protection lens coaxial with the coaxial nozzle and arranged in the coaxial nozzle, the molten pool isolation protection lens is arranged between the nozzle connecting block and the welding wire molten pool, the welding wire molten pool is communicated with the molten pool protection gas inlet pipeline, the flux feeding pipeline and the wire feeding pipe respectively, the laser beam passes through the molten pool isolation protection lens to irradiate the welding wire mixed with the flux to melt the welding wire, the melted welding wire flows into the welding wire molten pool in the molten pool protection gas, and the bottom of the welding wire molten pool is communicated with the welding end of the coaxial nozzle.

[0010] Preferably, the nozzle connecting block is respectively provided with a molten pool protection gas inlet port communicated with the molten pool protection gas inlet pipeline and a flux adding port communicated with the flux feeding pipeline, and the molten pool protection gas inlet port and the flux adding port are arranged on the two sides of the nozzle connecting block.

[0011] Preferably, the welding protection gas outlet device comprises a rotating shaft connector, a protection gas spray rotating shaft and a welding protection gas spray gun, the rotating shaft connector is installed on the laser processing assembly, one end of the protection gas spray rotating shaft is rotatably connected with the rotating shaft connector, the other end of the protection gas spray rotating shaft is provided with a mounting hole, the welding protection gas spray gun is arranged in the mounting hole, and the gas outlet of the welding protection gas spray gun is arranged close to the nozzle end of the coaxial nozzle assembly.

[0012] Preferably, the welding protection gas outlet device further comprises a molten pool monitoring unit, the molten pool monitoring unit comprises a molten pool monitoring camera, an illuminating device and a separator plate, the molten pool monitoring camera and the illuminating device are arranged on the laser processing assembly, and the separator plate is arranged in the laser processing assembly in a first direction as a reference, the welding laser passes through the separator plate to irradiate the welding wire molten pool, the illuminating light of the illuminating device is reflected to the welding wire molten pool through the separator plate, and the light reflected by the welding wire molten pool is transmitted to the molten pool monitoring camera through the reflection of the separator plate.

[0013] Preferably, the welding detection CCD is installed on one side of the laser emitting head, and the detection unit of the welding detection CCD is arranged towards the welding work surface.

[0014] Preferably, the mounting seat is provided with a plurality of groups of mounting hole positions, the laser processing assembly and the wire feeding assembly are fixed at the hole positions by locking members, and the mounting seat is further provided with a mechanical arm mounting hole position for connecting an external mechanical arm.

[0015] Compared with the prior art, the application has the following beneficial effects:

[0016] The battery liquid injection hole sealing laser welding device provided by the application solves the problems of virtual welding, pinholes, cracks and weld seam burst points caused by laser direct lithium battery liquid injection welding sealing, reduces the cleanliness requirement of the welding surface, greatly improves product quality and reduces lithium battery scrap. BRIEF DESCRIPTION OF DRAWINGS

[0017] Other features, objects and advantages of the application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the accompanying drawings:

[0018] Figure 1 It is a schematic diagram of a wire feeding laser welding processing device;

[0019] Figure 2 It is a front view of a wire feeding laser welding processing device;

[0020] Figure 3 It is a schematic diagram of a mounting seat;

[0021] Figure 4 It is a schematic diagram of a mounting seat connecting member;

[0022] Figure 5 It is a schematic diagram of a coaxial nozzle assembly;

[0023] Figure 6 It is a partial enlarged view of a coaxial nozzle assembly;

[0024] Figure 7 It is a schematic diagram of a molten pool monitoring;

[0025] Figure 8 It is a schematic diagram of a welding process.

[0026] BRIEF DESCRIPTION OF DRAWINGS

[0027] Mounting seat 1 Molten pool isolation protection lens 423

[0028] Mechanical arm mounting hole 11 Molten pool protection gas inlet pipeline 424

[0029] Laser processing assembly hole position 12 Welding wire molten pool 425

[0030] Wire feeding assembly hole position 13 Liquid welding solvent 426

[0031] Laser processing assembly 2 Laser path 427

[0032] Laser fiber 21 Welding protection gas outlet device 5

[0033] Laser processing head 22 Rotation shaft connector 51

[0034] Laser exit head 23 Protection gas spray gun rotation shaft 52

[0035] Wire feeding assembly 3 Welding protection gas spray gun 53

[0036] Sealing box 31 Molten pool monitoring unit 6

[0037] Disc-shaped welding wire 32 Molten pool monitoring camera 60

[0038] Wire feeding roller 33 Observation mirror 61

[0039] Wire feeding conduit 34 Monitoring path 62

[0040] Coaxial nozzle assembly 4 Coaxial illumination device 63

[0041] Nozzle connecting block 41 Separator 64

[0042] Soldering flux adding port 411 Coaxial illumination path 65

[0043] Molten pool protection gas inlet port 412 Battery 7

[0044] Coaxial nozzle 42 Sealing nail 71

[0045] Laser beam 421 Lithium battery liquid injection port 72

[0046] Soldering flux feeding pipe 422 Welding path 73

[0047] Welding detection CCD 74 DETAILED DESCRIPTION

[0048] The present application will be described in detail below with specific embodiments. The following embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any form. It should be pointed out that those skilled in the art can make several changes and improvements without departing from the concept of the present application. These all belong to the protection scope of the present application.

[0049] The present application provides a battery liquid injection hole sealing laser welding device, referring to Figure 1 and Figure 2, including: mounting seat 1, laser processing assembly 2, wire feeding assembly 3, coaxial nozzle assembly 4 and welding protection gas outlet device 5;Laser processing assembly 2 and wire feeding assembly 3 are respectively installed at both ends of mounting seat 1, coaxial nozzle assembly 4 is installed at the laser output end of laser processing assembly 2, wire feeding assembly 3 communicates with coaxial nozzle assembly 4 and part of the welding wire in wire feeding assembly 3 enters coaxial nozzle assembly 4, welding protection gas outlet device 5 is installed on laser processing assembly 2, and the gas outlet of welding protection gas outlet device 5 is arranged close to the welding port of coaxial nozzle assembly 4. The laser generated by laser processing assembly 2 is injected into coaxial nozzle assembly 4, the welding wire entering coaxial nozzle assembly 4 is melted to seal the liquid injection hole of lithium battery, and the welding stability of the molten welding wire is better than that of laser direct welding without welding wire, and the problems of virtual welding, pinhole, crack and weld burst caused by laser direct welding of liquid injection hole are solved. Welding protection gas outlet device 5 prevents liquid welding solvent 426 from being oxidized by contacting with air during welding.

[0050] Referring to Figure 3 , specifically, three groups of hole positions are arranged on mounting seat 1, which are mechanical hand mounting hole 11, laser processing assembly hole position 12 and wire feeding assembly hole position 13, mechanical hand mounting hole 11 is used for fixed connection with the end face of any mechanical arm with mounting hole, laser processing assembly hole position 12 is used for fixed connection with laser processing assembly 2, and wire feeding assembly hole position 13 is used for fixed connection with wire feeding assembly 3.

[0051] As Figure 4 , laser processing assembly 2 is used for emitting laser to coaxial nozzle assembly 4, specifically, laser processing assembly 2 includes laser optical fiber 21, laser processing head 22 and laser emitting head 23 arranged coaxially along the first direction, laser optical fiber 21 is installed on the incident port at the top of laser processing head 22 along the first direction, the bottom of laser processing head 22 is connected with laser emitting head 23, and laser emitting head 23 is connected with the laser input end of coaxial nozzle assembly 4, wherein laser processing head 22 is fixed on mounting seat 1 through laser processing assembly hole position 12. Laser emitting head 23 can adopt continuous fiber laser and pulse fiber laser, and can be configured according to actual welding needs.

[0052] Referring to Figure 4The wire feeding assembly 3 provides the welding wire raw material required by the coaxial nozzle assembly 4 for welding. Specifically, the wire feeding assembly 3 mainly includes a disc-shaped welding wire 32, a wire feeding roller 33, and a wire feeding conduit 34. The wire feeding roller 33 is installed on the rotating shaft of the wire feeding motor, which provides driving force for the wire feeding roller 33 through the wire feeding motor to control the forward and reverse rotation of the wire feeding roller 33, ensuring the feeding and feeding of the material. The speed of the wire feeding motor can be controlled according to the actual welding requirements, and the motor wire feeding accuracy is ±0.2 mm. The wire feeding roller 33 is installed between the wire feeding conduit 34 and the wire feeding motor. One end of the wire feeding conduit 34 is in communication with the coaxial nozzle assembly 4. The welding wire on the disc-shaped welding wire 32 is wound on the wire feeding roller 33 and passes through the wire feeding conduit 34 into the coaxial nozzle assembly 4. The material of the disc-shaped welding wire 32 includes but is not limited to aluminum, tin, copper, etc. Further, the wire feeding assembly 3 also includes a sealed box 31, which is installed before the equipment is running to form a closed space, and the disc-shaped welding wire 32 and the wire feeding roller 33 are located in the sealed box 31, which can prevent the welding wire from being oxidized. One end of the wire feeding conduit 34 is in communication with the coaxial nozzle assembly 4, and the other end of the wire feeding conduit 34 is in communication with the sealed box 31, and the welding wire on the disc-shaped welding wire 32 is wound on the wire feeding roller 33 and can pass through the wire feeding conduit 34 into the coaxial nozzle assembly 4. During welding, the entire wire feeding assembly 3 is in a fully sealed state, and the wire feeding assembly 3 controls the wire feeding speed by controlling the speed of the wire feeding motor.

[0053] Referring to Figure 4 , Figure 5 and Figure 6 , the coaxial nozzle assembly 4 receives the laser beam 421 emitted by the laser processing assembly 2 and the welding wire transmitted by the wire feeding assembly 3 to generate the welding wire solvent required for welding. Specifically, the coaxial nozzle assembly 4 includes a nozzle connecting block 41 and a coaxial nozzle 42. The nozzle connecting block 41 is fixedly connected to the laser exit head 23 in the laser processing assembly 2 at the top in the first direction, receives the laser beam 421 emitted by the laser processing assembly 2, and is connected to the coaxial nozzle 42 at the bottom in the first direction.

[0054] Referring to Figure 5The coaxial nozzle 42 is provided with a molten pool protection gas inlet pipeline 424, a flux feeding pipeline 422, a welding wire molten pool 425, and a molten pool isolation protection lens 423 coaxially arranged around the coaxial nozzle 42. In the first direction, the molten pool isolation protection lens 423 is arranged between the nozzle connecting block 41 and the welding wire molten pool 425. The welding wire molten pool 425 is in communication with the molten pool protection gas inlet pipeline 424, the flux feeding pipeline 422, and the wire feeding conduit 34. The laser beam 421 passes through the molten pool isolation protection lens 423 to irradiate the welding wire mixed with the flux to melt the welding wire. The molten welding wire flows into the welding wire molten pool 425 in the presence of the protection gas. The molten pool isolation protection lens 423 forms a closed space for the welding wire molten pool 425 to prevent the laser exit head 23 from being damaged by the high-temperature and high-pressure gas formed in the welding wire molten pool 425 during the operation of the equipment. The flux and the molten pool protection gas increase the welding quality and effect. At the bottom of the welding wire molten pool 425, the welding wire molten pool 425 is in communication with the welding end of the coaxial nozzle 42. In use, the molten pool protection gas first enters the welding wire molten pool 425 when the machine is started, followed by the coiled welding wire 32 and the flux, and finally the laser beam 421 radiates to melt the coiled welding wire 32 to form the liquid welding solvent 426 to drop into the welding wire molten pool 425.

[0055] The nozzle connecting block 41 is provided with a molten pool protection gas inlet 412 in communication with the molten pool protection gas inlet pipeline 424 and a flux adding port 411 in communication with the flux feeding pipeline 422. The molten pool protection gas inlet 412 and the flux adding port 411 are arranged on the two sides of the nozzle connecting block 41, respectively.

[0056] The welding protection gas outlet device 5 includes a rotating shaft connector 51, a protection gas spray rotating shaft 52, and a welding protection gas spray 53. The rotating shaft connector 51 is welded to the laser processing assembly 2. One end of the protection gas spray rotating shaft 52 is rotatably connected to the rotating shaft connector 51 by a pin, so that it can rotate up and down by 180°. The other end of the protection gas spray rotating shaft 52 is provided with a mounting hole. The welding protection gas spray 53 is arranged in the mounting hole. The gas outlet of the welding protection gas spray 53 is arranged close to the nozzle end of the coaxial nozzle assembly 4. The protection gas spray 53 can be adjusted according to the different welding positions and directions. The protection gas includes but is not limited to argon, nitrogen, carbon dioxide, etc., which is determined according to the material of the coiled welding wire 32.

[0057] During welding, the welding wire molten pool 425 is a closed space. By changing the gas pressure of the molten pool protection gas, the gas pressure in the welding wire molten pool 425 is changed, so as to control the liquid welding solvent 426 to be sprayed from the coaxial nozzle 42 to the welding position.

[0058] The laser welding device for sealing the battery injection hole also includes a molten pool monitoring unit 6, which is installed on one side of the laser processing component 2. The molten pool monitoring unit 6 monitors the specific state of the molten pool 425 of the welding wire in real time, and the molten pool monitoring unit 6 adopts a CCD industrial camera.

[0059] The molten pool detection unit 6 includes a molten pool detection camera 60, an observation mirror 61, an illumination device 63, and a separator plate 64, for reference. Figure 7 As shown, the separator plate 64 is tilted at 45° inside the laser processing assembly 2 with the first direction as the reference. The laser beam 421 can pass through the separator plate 64, while light of other wavelengths is reflected when it passes through the surface of the separator plate 64. The laser beam 421 passes through the separator plate 64 and enters the weld pool 425, and the laser path 427 is shown in the figure. The weld pool detection camera 60 and the illumination device 63 are set on the laser processing assembly 2. The illumination device 63 is located between the separator plate 64 and the observation mirror 61. The illumination device 63 is installed on the side wall of the laser channel inside the laser processing assembly 2. The illumination light from the illumination device 63 can be reflected by the separator plate 64 to reach the weld pool 425.

[0060] In one specific embodiment, the lighting device 63 adopts a coaxial lighting device, and the coaxial lighting path 65 is shown in the figure. The light reflected by the welding wire molten pool 425 is reflected by the separator plate 64. After passing through the coaxial lighting device, the reflected light is reflected by the observation mirror 61 and finally enters the light sensing entrance of the molten pool detection camera 60. The monitoring path 62 is shown in the figure.

[0061] A welding inspection CCD 74 is also installed on the laser emitter head 23. The welding inspection CCD 74 is fixed to the laser emitter head 23 by a connecting plate, and the detection unit of the welding inspection CCD 74 is set facing the welding work surface. The welding inspection CCD 74 illuminates the welding surface of the entire battery filling hole to detect whether there are defects such as incomplete welds, pinholes, cracks, and weld seams.

[0062] Specifically, such as Figure 8 As shown, during the welding process of battery sample 7, welding detection CCD 74 detects the welding quality. The sealing nail 71 is placed at the liquid injection port 72 of battery 7. The welding machine moves down to the welding point according to the detection signal given by welding detection CCD 74 and performs welding according to the welding path 73 given in the program. The welding protection gas exhaust device 55 continuously sprays gas at the welding point to improve the welding quality.

[0063] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like refer to the orientation or positional relationship shown in the drawings, and are only intended to facilitate the description of the present application and simplify the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0064] The specific embodiments of the present application are described above. It should be understood that the present application is not limited to the above specific embodiments, and various changes or modifications can be made by those skilled in the art within the scope of the claims, which do not affect the essential content of the present application. The embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other without conflict, provided that they do not conflict.

Claims

1. A laser welding device for sealing battery injection holes, characterized in that, include: The assembly comprises a mounting base, a laser processing component, a wire feeding component, a coaxial nozzle component, and a welding protective gas venting device. The laser processing component and the wire feeding component are respectively mounted at both ends of the mounting base. The coaxial nozzle component is mounted at the laser output end of the laser processing component. The wire feeding component is connected to the coaxial nozzle component, and part of the welding wire in the wire feeding component enters the coaxial nozzle component. The welding protective gas venting device is mounted on the laser processing component, and the gas outlet of the welding protective gas venting device is located close to the welding port of the coaxial nozzle component. The coaxial nozzle assembly includes a nozzle connecting block and a coaxial nozzle. The nozzle connecting block is connected to the top of the laser processing assembly along a first direction and receives the laser beam emitted by the laser processing assembly. The coaxial nozzle is provided with a molten pool shielding gas inlet pipe, a flux inlet pipe, a welding wire molten pool, and a molten pool isolation protective lens that is coaxial with the coaxial nozzle and surrounds it. The molten pool isolation protective lens is located between the nozzle connecting block and the welding wire molten pool. The welding wire molten pool is connected to the molten pool shielding gas inlet pipe, the flux inlet pipe, and the wire feeding guide pipe, respectively. The laser beam passes through the molten pool isolation protective lens and irradiates the welding wire mixed with flux, causing it to melt. The melted welding wire flows into the welding wire molten pool containing molten pool shielding gas. The bottom of the welding wire molten pool is connected to the welding end of the coaxial nozzle.

2. The laser welding device for sealing battery injection holes according to claim 1, characterized in that: The laser processing assembly includes a laser fiber, a laser processing head, and a laser output head arranged coaxially along a first direction. The laser fiber is installed at the top entrance of the laser processing head, the bottom of the laser processing head is connected to the laser output head, the laser output head is connected to the laser input end of the coaxial nozzle assembly, and the laser processing head is connected to the mounting base.

3. The laser welding device for sealing battery injection holes according to claim 1, characterized in that: The wire feeding assembly includes a wire feeding motor, a wire feeding roller, and a wire feeding guide tube. The wire feeding motor drives the wire feeding roller to rotate. One end of the wire feeding guide tube is connected to the discharge port of the wire feeding roller, and the other end of the wire feeding guide tube is connected to the coaxial nozzle assembly. The welding wire on the coiled welding wire is wound on the wire feeding roller and passes through the discharge port of the wire feeding roller, through the wire feeding guide tube, and into the coaxial nozzle assembly.

4. The laser welding device for sealing battery injection holes according to claim 3, characterized in that: The wire feeding assembly also includes a sealed box, in which the wire feeding motor, wire feeding roller, and welding wire are all housed. One end of the wire feeding guide tube is connected to the outlet of the wire feeding roller by communicating with the sealed box.

5. The laser welding device for sealing battery injection holes according to claim 1, characterized in that: The nozzle connecting block is provided with a molten pool protective gas inlet that is connected to the molten pool protective gas inlet pipe, and a flux addition port that is connected to the flux feed pipe. The molten pool protective gas inlet and the flux addition port are respectively located on both sides of the nozzle connecting block.

6. The laser welding device for sealing battery injection holes according to claim 1, characterized in that: The welding protective gas outlet device includes a rotating shaft connector, a protective gas spray gun rotating shaft, and a welding protective gas spray gun; the rotating shaft connector is installed on the laser processing assembly, one end of the protective gas spray gun rotating shaft is rotatably connected to the rotating shaft connector, the other end of the protective gas spray gun rotating shaft is provided with a mounting hole, the welding protective gas spray gun is inserted into the mounting hole, and the gas outlet of the welding protective gas spray gun is located near the nozzle end of the coaxial nozzle assembly.

7. The laser welding device for sealing battery injection holes according to claim 1, characterized in that: It also includes a molten pool monitoring unit, which includes a molten pool detection camera, an illumination device, and a separator plate. The molten pool detection camera and the illumination device are mounted on the laser processing assembly. The separator plate is tilted inside the laser processing assembly with a first direction as the reference. The welding laser passes through the separator plate and enters the molten pool of the welding wire. The illumination light from the illumination device is reflected by the separator plate and reaches the molten pool of the welding wire. The light reflected by the molten pool of the welding wire is reflected by the separator plate and transmitted to the molten pool detection camera.

8. The laser welding device for sealing battery injection holes according to claim 1, characterized in that: It also includes a welding inspection CCD, which is installed on one side of the laser emitter head, with the inspection unit of the welding inspection CCD facing the welding work surface.

9. The laser welding device for sealing battery injection holes according to claim 1, characterized in that: The mounting base is provided with multiple sets of mounting holes. The laser processing component and the wire feeding component are both fixed to the holes by locking components. The mounting base is also provided with robot mounting holes for connecting an external robot.

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