Lithium battery cap laser welding device and welding method thereof

Abstract

The invention provides a lithium battery cap laser welding device and a welding method thereof, and belongs to the technical field of laser welding. The lithium battery cap laser welding device comprises a bottom plate, an operation table is installed on the top face of the bottom plate, a guide rail is installed on the top face of the operation table, supporting legs are connected to the top of the guide rail in a clamped mode, a welding table is fixedly installed on the top faces of the supporting legs, and a welding jig is arranged on the top face of the welding table. And a laser welding mechanism is arranged on the top surface of the bottom plate. Transmission is achieved between a motor and a third transmission shaft, a first swing arm is driven to swing, a first driven disc is driven to do circular motion along the outer portion of a first driving disc through a first connecting toothed belt, then a second swing arm is driven to swing, and the working principle between a second driving disc and a second driven disc is the same as the above working principle. And then the welding table can be driven to move back and forth on the top face of the operation table, and automatic welding and feeding of battery shells and caps are achieved.

Description

Technical Field

[0001] This invention relates to the field of laser welding technology, and more specifically, to a laser welding device and welding method for lithium battery caps. Background Technology

[0002] Laser welding of lithium battery caps is a crucial step in lithium battery manufacturing. It is mainly used to firmly connect the cap to other battery components. Due to its high energy density, fast welding speed, and low heat input, laser welding has become a commonly used connection technology in lithium battery packaging. The laser beam is focused on the joint between the cap and the battery casing through a precise optical system. The welding area is instantly heated to a high temperature, and the material melts. The molten metal forms a molten pool with the cap surface. The molten pool cools rapidly and forms a weld joint. After the laser is extinguished, the molten area cools and solidifies, forming a strong metal connection.

[0003] However, existing lithium batteries still have some problems in the laser welding process. For example, existing laser welding equipment requires manual placement of the lithium battery casing and cap under the laser welding head for welding. Manual placement is prone to misoperation, which may cause the laser welding head to start during placement, thereby increasing the risk of welding. In addition, after welding, the lithium battery and cap need to be cooled quickly to improve the welding stability. However, existing laser welding equipment generally allows natural cooling, which increases the thermal stress between the two after welding and affects the subsequent welding effect. Summary of the Invention

[0004] To overcome the above deficiencies, the present invention provides a laser welding device and welding method for lithium battery caps that overcomes or at least partially solves the above technical problems.

[0005] This invention is implemented as follows: This invention provides a laser welding device for lithium battery caps, comprising a base plate, an operating table mounted on the top surface of the base plate, a guide rail mounted on the top surface of the operating table, a support leg snapped onto the top of the guide rail, a welding table fixedly mounted on the top surface of the support leg, a welding fixture provided on the top surface of the welding table, a lithium battery module placed inside the welding fixture, a battery casing stacked inside the lithium battery module, a cap placed on the top surface of the battery casing, and a laser welding mechanism provided on the top surface of the base plate. The laser welding mechanism includes a Z-axis moving frame, which is movably mounted on the top surface of the base plate. A connecting rod is installed on the inner side of the Z-axis moving frame, an X-axis moving frame is installed on the outer side of the connecting rod, and a Y-axis moving frame is installed on the outer side of the X-axis moving frame. A laser welding head is installed on one side of the Y-axis moving frame. The laser welding mechanism is configured for laser welding between the battery casing and the cap.

[0006] In a preferred embodiment, the operating table is provided with a welding feeding mechanism, which includes a base. The base is fixedly installed on the top surface of the base plate. An L-shaped mounting bracket is fixedly installed on the top surface of the base. A mounting seat is installed inside the L-shaped mounting bracket. A drive shaft is installed inside the mounting seat. A drive shaft is provided on one side of the base. The drive shaft and the drive shaft are meshed with each other by bevel gears.

[0007] In a preferred embodiment, a drive disc is mounted on the other end of the drive shaft 2, a swing arm is provided on the outer side of the drive disc 1, a driven disc is mounted on one end of the swing arm 1, a connecting toothed belt is sleeved between the driven disc 1 and the drive disc 1, and a swing arm 2 is connected to one end of the swing arm 1.

[0008] In a preferred embodiment, a mounting base two is installed on one side of the base, and a drive shaft three is installed inside the mounting base two. One end of the drive shaft three meshes with the other end of the drive shaft one through a bevel gear. The drive shaft three can be driven by a motor. A drive shaft four is installed on one side of the base, and the other end of the drive shaft three meshes with one end of the drive shaft four through a bevel gear.

[0009] In a preferred embodiment, a drive disc two is mounted on the other end of the drive shaft four, a swing arm three is provided on the outer side of the drive disc two, the other end of the swing arm three is connected to a driven disc two, and a connecting toothed belt two is sleeved between the connecting toothed belt two and the drive disc two.

[0010] In a preferred embodiment, one end of the swing arm three is connected to a swing arm four, and a translation frame is provided between the active disk one and the active disk two. The bottom surface and one side surface of the translation frame are respectively fixedly installed with a protrusion two and a protrusion one. The other end of the swing arm two is sleeved on the outer surface of the protrusion one, and the other end of the swing arm four is sleeved on the outer surface of the protrusion two. A through groove is opened on one side surface of the operating table, and an L-shaped connecting frame is movably engaged inside the through groove. One end of the L-shaped connecting frame is fixedly connected to one side surface of the translation frame, and the other end of the L-shaped connecting frame is fixedly connected to one side surface of the welding table.

[0011] In a preferred embodiment, the top surface of the operating table is provided with a stress relief mechanism, which includes two sets of fixed frames. A rotating shaft is rotatably installed between the two sets of fixed frames. A pulley is installed on the outer surface of each of the two rotating shafts. A transmission belt is sleeved inside the two pulleys. A limit frame is installed on the outer side of each fixed frame. Two toothed plates are movably engaged inside the limit frame. The two toothed plates correspond to the two rotating shafts respectively. A spring is fixedly connected between the two toothed plates.

[0012] In a preferred embodiment, half gears are fixedly installed at both ends of the rotating shaft, and the half gears are located above the fixed frame. A C-shaped frame is fixedly installed on the top surface of the gear plate. A box is provided on one side of the C-shaped frame. A connecting pipe is fixedly connected to the top surface of the box. A rectangular tube is fixedly connected to the other end of the connecting pipe. A hollow frame is fixedly connected to the top surface of the rectangular tube. An exhaust frame is fixedly connected to the top of the hollow frame. Two locking plates are movably engaged inside the box. An air inlet pipe is fixedly connected to one side of the box. A connecting block one is fixedly connected to one side surface of the locking plate. The other end of the connecting block one is fixedly connected to the bottom surface of the C-shaped frame. A connecting block two is fixedly connected to the bottom surface of the welding table. A limit box is fixedly connected to the bottom surface of the connecting block two.

[0013] In a preferred embodiment, the limiting box has an internal built-in block, and each internal built-in block has a snap-fit ​​post that is movably inserted into it. Both the limiting box and the internal built-in block are trapezoidal in shape at one end, and a spring is fixedly connected between one side surface of the internal built-in block and the inner side surface of the limiting box.

[0014] A method for laser welding lithium battery caps includes the following steps: S1: Place the lithium battery module to be welded into the inside of the welding fixture for clamping and fixing. Then, neatly place the cap on the top surface of the battery casing inside the lithium battery module. The welding feeding mechanism drives the welding table to move towards the laser welding mechanism. Then, by controlling the operation of the laser welding mechanism, the battery casing and the cap are welded. After the welding is completed, the welding feeding mechanism continues to operate, moving the welding table away from the bottom of the laser welding mechanism to achieve the unloading operation. S2: Transmission is achieved by using a motor and a transmission shaft three. When the motor is started, the transmission shaft three rotates, which in turn drives the swing arm one to swing. This drives the driven disk one to move in a circle along the outside of the active disk one via the connecting toothed belt one, which in turn drives the swing arm two to swing. The working principle between the active disk two and the driven disk two is the same as described above. This allows the welding table to move back and forth on the top surface of the operating table, enabling automatic welding and feeding of the battery casing and cap. S3: When the welding table moves away from the laser welding mechanism, it enables the two toothed plates inside the limiting frame to move in the same direction, driving the C-shaped frame to move. Under the action of the connecting block one, the two snap-fit ​​plates move towards each other inside the box, compressing the air between the two snap-fit ​​plates and squeezing it into the inside of the connecting tube. Finally, under the action of the connecting tube, rectangular tube, hollow frame and exhaust frame, the air is blown out towards the welded battery casing and cap, allowing the heat of the battery casing and cap to dissipate quickly. S4: When the welding table moves in the opposite direction to the laser welding mechanism, the built-in block moves continuously towards the direction of spring two under the action of friction, and the distance between the two locking pins will increase. Conversely, when the welding table moves away from the laser welding mechanism, the built-in block moves continuously away from spring two, and thus the transmission belt is clamped under the shape of the limit box and the built-in block, driving the pulley to rotate. This ensures that during the feeding welding process, the cap will not be blown off the outer surface of the battery casing by air.

[0015] The present invention provides a laser welding device and welding method for lithium battery caps, the beneficial effects of which include: 1. By setting up a welding feeding mechanism, the transmission is achieved through the motor and the transmission shaft three. When the motor is started, the transmission shaft three rotates, which drives the swing arm one to swing. This drives the driven plate one to move in a circle along the outside of the active plate one through the connecting toothed belt one, which in turn drives the swing arm two to swing. The working principle between the active plate two and the driven plate two is the same as described above. This enables the welding table to move back and forth on the top surface of the operating table, achieving automatic welding and feeding of the battery casing and cap.

[0016] 2. By setting up a stress relief mechanism, when the welding table moves away from the laser welding mechanism, the two toothed plates inside the limiting frame move in the same direction, driving the C-shaped frame to move. Under the action of the connecting block, the two snap-fit ​​plates move towards each other inside the box, compressing the air between the two snap-fit ​​plates and squeezing it into the inside of the connecting tube. Finally, under the action of the connecting tube, rectangular tube, hollow frame and exhaust frame, the air is blown out towards the welded battery casing and cap, allowing the heat of the battery casing and cap to dissipate quickly.

[0017] 3. By setting a limit box, when the welding table moves in the opposite direction to the laser welding mechanism, the built-in block can move continuously towards the direction of spring two under the action of friction, and the distance between the two locking posts will increase. Conversely, when the welding table moves away from the laser welding mechanism, the built-in block can move continuously away from spring two. Thus, the transmission belt can be clamped by the shape of the limit box and the built-in block, driving the pulley to rotate. This ensures that during the feeding welding process, air will not blow the cap off the outer surface of the battery casing. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is an overall perspective view provided by an embodiment of the present invention; Figure 2 A schematic diagram of the overall front view structure provided for an embodiment of the present invention; Figure 3 A schematic diagram of the welding feeding mechanism provided for an embodiment of the present invention; Figure 4 This is a side view of the welding feeding structure provided in an embodiment of the present invention. Figure 5 A schematic diagram of the stress relief mechanism provided for an embodiment of the present invention; Figure 6 A schematic diagram of the front view structure of the box provided for an embodiment of the present invention; Figure 7 A schematic diagram of the overall side view structure provided for an embodiment of the present invention; Figure 8 A schematic diagram of the limiting box structure provided for an embodiment of the present invention.

[0020] In the diagram: 1. Base plate; 2. Operating table; 3. Guide rail; 4. Support leg; 5. Welding table; 6. Welding fixture; 7. Lithium battery module; 8. Battery casing; 9. Cap; 10. Laser welding mechanism; 1001. Z-axis moving frame; 1002. Connecting rod; 1003. X-axis moving frame; 1004. Y-axis moving frame; 1005. Laser welding head; 11. Through slot; 12. Welding feeding mechanism; 1201. Base; 1202. L-shaped mounting bracket; 1203. Mounting base one; 1204. Drive shaft one; 1205. Drive shaft two; 1206. Drive disc one; 1207. Swing arm one; 1208. Driven disc one; 1209. Connecting toothed belt one; 1210. Swing arm two; 1211. Translation frame; 1212. Protrusion one; 1213. L-shaped connecting frame; 1214. Mounting base two; 1215. Drive shaft three; 1216. 1217. Drive shaft 4; 1218. Driven disc 2; 1219. Swing arm 3; 1220. Swing arm 4; 1221. Driven disc 2; 1222. Connecting toothed belt 2; 1222. Protrusion 2; 13. Stress relief mechanism; 1301. Fixed frame; 1302. Rotating shaft; 1303. Pulley; 1304. Drive belt; 1305. Half gear; 1306. Limiting frame; 1307. Toothed plate; 1308. C-shaped frame; 1309. Spring 1; 1310. Housing; 1311. Connecting pipe; 1312. Rectangular tube; 1313. Hollow frame; 1314. Exhaust frame; 1315. Intake pipe; 1316. Snap-fit ​​plate; 1317. Connecting block 1; 1318. Limiting box; 1319. Internal block; 1320. Snap-fit ​​post; 1321. Spring 2; 1322. Limiting sleeve; 1323. Limiting post; 1324. Connecting block 2. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Reference Figures 1-8The present invention provides a technical solution: a laser welding device for lithium battery caps, including a base plate 1, an operating table 2 installed on the top surface of the base plate 1, a guide rail 3 installed on the top surface of the operating table 2, a support leg 4 snapped onto the top of the guide rail 3, a welding table 5 fixedly installed on the top surface of the support leg 4, a welding fixture 6 provided on the top surface of the welding table 5, a lithium battery module 7 placed inside the welding fixture 6, a battery casing 8 stacked inside the lithium battery module 7, a cap 9 placed on the top surface of the battery casing 8, and a laser welding mechanism 10 provided on the top surface of the base plate 1. The laser welding mechanism 10 includes a Z-axis moving frame 1001, which is movably mounted on the top surface of the base plate 1. A connecting rod 1002 is installed inside the Z-axis moving frame 1001, an X-axis moving frame 1003 is installed outside the connecting rod 1002, a Y-axis moving frame 1004 is installed outside the X-axis moving frame 1003, and a laser welding head 1005 is installed on one side of the Y-axis moving frame 1004. The laser welding mechanism 10 is configured for laser welding between the battery casing 8 and the cap 9.

[0023] During operation, in actual use, the lithium battery module 7 to be welded is first placed inside the welding fixture 6 for clamping and fixing. After fixing, the cap 9 is neatly placed on the top surface of the battery casing 8 inside the lithium battery module 7. After placement, the welding feeding mechanism 12 can move the welding table 5 towards the laser welding mechanism 10. When the welding table 5 reaches the laser welding mechanism 10, the welding feeding mechanism 12 stops. Then, by controlling the operation of the laser welding mechanism 10, the welding operation is performed on the battery casing 8 and the cap 9. During the welding process, laser welding... The head 1005 can achieve three-axis movement under the action of the X-axis moving frame 1003, Y-axis moving frame 1004 and Z-axis moving frame 1001, so as to achieve the purpose of precise welding of multiple battery casings 8 and caps 9, thereby improving the welding efficiency of battery casings 8 and caps 9. After the welding is completed, the welding feeding mechanism 12 can be restarted to drive the welding table 5 to move away from the laser welding mechanism 10, and replace the lithium battery module 7 inside the welding fixture 6 to realize the next welding operation. Moreover, the guide rail 3 and support leg 4 can make the welding table 5 more stable during the movement.

[0024] The operating table 2 is equipped with a welding feeding mechanism 12, which includes a base 1201. The base 1201 is fixedly installed on the top surface of the base plate 1. An L-shaped mounting bracket 1202 is fixedly installed on the top surface of the base 1201. A mounting seat 1203 is installed inside the L-shaped mounting bracket 1202. A drive shaft 1204 is installed inside the mounting seat 1203. A drive shaft 2 1205 is provided on one side of the base 1201. The drive shaft 1 1204 and the drive shaft 2 1205 are meshed with each other by bevel gears. A drive disc 1206 is installed at the other end of the drive shaft 2 1205. A swing arm 1207 is provided on the outer side of the driving disc 1206. A driven disc 1208 is installed at one end of the swing arm 1207. A connecting toothed belt 1209 is sleeved between the driven disc 1208 and the driving disc 1206. A swing arm 1210 is connected to one end of the swing arm 1207. A mounting seat 1214 is installed on one side of the base 1201. A drive shaft 1215 is installed inside the mounting seat 1214. One end of the drive shaft 1215 meshes with the other end of the drive shaft 1204 through a bevel gear. The drive shaft 1215 can be driven by a motor. A drive shaft 1216 is mounted on one side of 201. The other end of drive shaft 1215 meshes with one end of drive shaft 1216 via bevel gears. A drive disc 1217 is mounted on the other end of drive shaft 1216. A swing arm 1218 is provided on the outer side of drive disc 1217. The other end of swing arm 1218 is connected to driven disc 1220. A connecting toothed belt 1221 is sleeved between drive disc 1217 and drive disc 1217. A swing arm 1219 is connected to one end of swing arm 1218. A drive disc 1206 is positioned between drive disc 1206 and drive disc 1217. A translation frame 1211 is provided. A second protrusion 1222 and a first protrusion 1212 are fixedly installed on the bottom surface and one side surface of the translation frame 1211, respectively. The other end of the second swing arm 1210 is sleeved on the outer surface of the first protrusion 1212, and the other end of the fourth swing arm 1219 is sleeved on the outer surface of the second protrusion 1222. A through groove 11 is opened on one side surface of the operating table 2. An L-shaped connecting frame 1213 is movably engaged inside the through groove 11. One end of the L-shaped connecting frame 1213 is fixedly connected to one side surface of the translation frame 1211, and the other end of the L-shaped connecting frame 1213 is fixedly connected to one side surface of the welding table 5.

[0025] During operation, transmission is achieved through a motor and drive shaft 1215. This means that starting the motor drives drive shaft 1215 to rotate, achieving electrical control. When the motor starts and drives drive shaft 1215, the bevel gears at both ends of drive shaft 1215 drive drive shafts 1204 and 1216 to rotate. When drive shaft 1204 rotates, the bevel gears drive drive shaft 2205 to rotate, which in turn causes swing arm 1207 to swing on one side of drive disc 1206. Drive shafts 1205 and 1216 are both mounted to base 1201 via positioning blocks. Drive discs 1206 and 1217 are fixedly mounted on the outside of the positioning blocks. Therefore, when swing arm 1207 swings, it drives the driven... Disc 1208 moves in a circular motion along the outside of active disc 1206 via connecting toothed belt 1209, thereby driving swing arm 1210 to swing. The working principle between active disc 1217 and driven disc 1220 is the same as described above. That is, when swing arm 1210 and swing arm 1219 swing, they can drive translation frame 1211 to move back and forth in parallel, thereby driving L-shaped connecting frame 1213 to move back and forth inside through slot 11. Since one end of L-shaped connecting frame 1213 is fixedly connected to welding table 5, it can drive welding table 5 to move back and forth on the top surface of operating table 2, thereby achieving the purpose of automatic welding and feeding of battery casing 8 and cap 9, replacing the drawback of existing manual feeding which is prone to danger, and thus greatly improving the overall safety of the device when laser welding battery casing 8 and cap 9.

[0026] The top surface of the operating table 2 is equipped with a stress relief mechanism 13. The stress relief mechanism 13 includes two sets of fixed frames 1301, with rotating shafts 1302 rotatably mounted between the two sets of fixed frames 1301. Pulleys 1303 are mounted on the outer surfaces of the two rotating shafts 1302, and transmission belts 1304 are sleeved inside the two pulleys 1303. Limit frames 1306 are mounted on the outer sides of the fixed frames 1301, and two toothed plates 1307 are movably engaged inside the limit frames 1306. The two toothed plates 1307 correspond to the two rotating shafts 1302 respectively, and a spring 1309 is fixedly connected between the two toothed plates 1307. Half gears 1305 are fixedly mounted at both ends of the rotating shafts 1302, and the half gears 1305 are located above the fixed frames 1301. A C-shaped frame 1308 is fixedly mounted on the top surface of the toothed plates 1307, and a side of the C-shaped frame 1308 is provided with... The enclosure 1310 has a housing 1310. A connecting pipe 1311 is fixedly connected to the top surface of the housing 1310. A rectangular pipe 1312 is fixedly connected to the other end of the connecting pipe 1311. A hollow frame 1313 is fixedly connected to the top surface of the rectangular pipe 1312. An exhaust frame 1314 is fixedly connected to the top of the hollow frame 1313. Two snap-fit ​​plates 1316 are movably snapped inside the housing 1310. An air inlet pipe 1315 is fixedly connected to one side of the housing 1310. A connecting block 1317 is fixedly connected to one side of the snap-fit ​​plate 1316. The other end of the connecting block 1317 is fixedly connected to the bottom surface of the C-shaped frame 1308. A connecting block 2 1324 is fixedly connected to the bottom surface of the welding table 5. A limit box 1318 is fixedly connected to the bottom surface of the connecting block 2 1324. One-way valves with opposite flow directions are installed on the outer surfaces of the connecting pipe 1311 and the air inlet pipe 1315.

[0027] During operation, as the welding table 5 moves back and forth on top of the operating table 2, it drives the stress relief mechanism 13 to operate. Specifically, when the welding table 5 moves towards the laser welding mechanism 10, the stress relief mechanism 13 is prevented from operating under the action of the limit box 1318. In other words, the stress relief mechanism 13 does not operate before welding. When welding is completed, that is, when the welding table 5 moves away from the laser welding mechanism 10, the transmission belt 1304 moves with the welding table 5 under the action of the limit box 1318, thereby driving the two sets of pulleys 1303 to rotate, which in turn drives the half gear 1305 to rotate. When the tooth groove of the half gear 1305 meshes with the tooth plate 1307, the two tooth plates 1307 inside the limit frame 1306 rotate in the same direction. The directional movement drives the C-shaped frame 1308 to move, thereby enabling the two snap-fit ​​plates 1316 to move towards each other inside the housing 1310 under the action of the connecting block 1317. This compresses the air between the two snap-fit ​​plates 1316 and forces it into the connecting pipe 1311. Finally, under the action of the connecting pipe 1311, rectangular pipe 1312, hollow frame 1313, and exhaust frame 1314, the air is blown out towards the welded battery casing 8 and cap 9, allowing the heat of the battery casing 8 and cap 9 to dissipate quickly. This allows the metal to shrink more evenly after welding, thereby reducing thermal deformation and significantly improving welding quality and component performance. This achieves the goal of quickly eliminating thermal stress in the battery casing 8 and cap 9 after welding, avoiding the problem of cracks caused by local overheating after welding.

[0028] The limiting box 1318 has an internal built-in block 1319. Each internal built-in block 1319 has a snap-fit ​​post 1320 that is movably inserted into it. One end of both the limiting box 1318 and the internal built-in block 1319 is trapezoidal. A spring 1321 is fixedly connected between one side surface of the internal built-in block 1319 and the inner side surface of the limiting box 1318. A limiting sleeve 1322 and a limiting post 1323 are provided inside the spring 1321. One end of the limiting sleeve 1322 is fixedly installed inside the limiting box 1318, and one end of the limiting post 1323 is fixedly installed on one side of the internal built-in block 1319. The internal built-in block 1319 is movably inserted into the inside of the limiting sleeve 1322.

[0029] During operation, the limiting box 1318 ensures that no wind blows onto the outside of the battery casing 8 and the cap 9 when the welding table 5 moves toward the laser welding mechanism 10. Specifically, when the welding table 5 moves toward the laser welding mechanism 10, the transmission belt 1304 passes through the internal block 1319 and the limiting box 1318, and is located between the two locking posts 1320. When the welding table 5 moves in the opposite direction to the laser welding mechanism 10, the internal block 1319 continuously moves toward the spring 1321 under the action of friction. The distance between the two locking posts 1320 is... It will become larger. Conversely, when the welding table 5 moves away from the laser welding mechanism 10, the built-in block 1319 can continuously move away from the spring 1321. This allows the transmission belt 1304 to be clamped under the shape of the limit box 1318 and the built-in block 1319, driving the pulley 1303 to rotate. This ensures that during the feeding welding process, the cap 9 will not be blown off the outer surface of the battery casing 8. During the welding discharge process, the thermal stress between the battery casing 8 and the cap 9 is eliminated, thereby further improving the overall practicality of the device.

[0030] A method for laser welding lithium battery caps includes the following steps: S1: Place the lithium battery module 7 to be welded into the welding fixture 6 for clamping and fixing, and then neatly place the cap 9 on the top surface of the battery shell 8 inside the lithium battery module 7. The welding feeding mechanism 12 drives the welding table 5 to move towards the laser welding mechanism 10. Then, by controlling the operation of the laser welding mechanism 10, the battery shell 8 and the cap 9 are welded. After the welding is completed, the welding feeding mechanism 12 continues to operate, driving the welding table 5 away from the bottom of the laser welding mechanism 10 to achieve the unloading operation. S2: Transmission is achieved through the motor and the transmission shaft 1215. When the motor is started, the transmission shaft 1215 is rotated, which drives the swing arm 1207 to swing. This drives the driven disk 1208 to make a circular motion along the outside of the active disk 1206 through the connecting toothed belt 1209, which in turn drives the swing arm 1210 to swing. The working principle between the active disk 1217 and the driven disk 1220 is the same as above. This enables the welding table 5 to move back and forth on the top surface of the operating table 2, and automatically welds and feeds the battery casing 8 and the cap 9. S3: When the welding table 5 moves away from the laser welding mechanism 10, it enables the two toothed plates 1307 inside the limit frame 1306 to move in the same direction, driving the C-shaped frame 1308 to move. Thus, under the action of the connecting block 1317, the two snap-fit ​​plates 1316 move towards each other inside the housing 1310, compressing the air between the two snap-fit ​​plates 1316 and squeezing it into the connecting tube 1311. Finally, under the action of the connecting tube 1311, the rectangular tube 1312, the hollow frame 1313 and the exhaust frame 1314, the air is blown out towards the welded battery casing 8 and the cap 9, so that the heat of the battery casing 8 and the cap 9 can be dissipated quickly. S4: When the welding table 5 moves in the opposite direction to the laser welding mechanism 10, the built-in block 1319 moves continuously towards the spring 1321 under the action of friction, and the distance between the two locking posts 1320 will increase. Conversely, when the welding table 5 moves away from the laser welding mechanism 10, the built-in block 1319 moves continuously away from the spring 1321, and thus the transmission belt 1304 is clamped under the shape of the limit box 1318 and the built-in block 1319, driving the pulley 1303 to rotate. This ensures that during the feeding welding process, the cap 9 will not be blown off the outer surface of the battery casing 8.

[0031] Specifically, the working process or principle of the lithium battery cap laser welding device and its welding method is as follows: During use, the lithium battery module 7 to be welded is placed inside the welding fixture 6 for clamping and fixing. Then, the cap 9 is neatly placed on the top surface of the battery casing 8 inside the lithium battery module 7. The welding feeding mechanism 12 drives the welding table 5 towards the laser welding mechanism 10. By controlling the operation of the laser welding mechanism 10, the battery casing 8 and the cap 9 are welded. After welding is completed, the continuous operation of the welding feeding mechanism 12 moves the welding table 5 away from below the laser welding mechanism 10, achieving the unloading operation. The transmission is achieved through the connection between the motor and the transmission shaft 1215. When the motor starts and drives the transmission shaft 1215 to rotate, it causes the swing arm 1207 to swing, which in turn causes the driven disk 1208 to move in a circular motion along the outside of the driving disk 1206 via the connecting toothed belt 1209. This, in turn, causes the swing arm 1210 to swing. The working principle between the driving disk 1217 and the driven disk 1220 is the same as described above. This allows the welding table 5 to move back and forth on the top surface of the operating table 2, automatically welding and feeding the battery casing 8 and the cap 9. When the welding table 5 moves away from the laser welding mechanism 10, it enables... The two toothed plates 1307 inside the limiting bracket 1306 move in the same direction, driving the C-shaped bracket 1308 to move. This allows the two snap-fit ​​plates 1316 to move towards each other inside the housing 1310 under the action of the connecting block 1317, compressing the air between the two snap-fit ​​plates 1316 and forcing it into the connecting pipe 1311. Finally, through the action of the connecting pipe 1311, rectangular pipe 1312, hollow bracket 1313, and exhaust bracket 1314, the air is blown out towards the welded battery casing 8 and cap 9, allowing the heat from the battery casing 8 and cap 9 to dissipate quickly. When the welding table 5 moves towards the laser welding... When the receiving mechanism 10 moves in the opposite direction, the built-in block 1319 can move continuously towards the spring 1321 under the action of friction, and the distance between the two locking posts 1320 will increase. Conversely, when the welding table 5 moves away from the laser welding mechanism 10, the built-in block 1319 can move continuously away from the spring 1321, thereby clamping the transmission belt 1304 under the shape of the limiting box 1318 and the built-in block 1319, driving the pulley 1303 to rotate, thus achieving the goal of preventing air from blowing the cap 9 off the outer surface of the battery casing 8 during the feeding welding process.

[0032] It should be noted that the lithium battery module 7, battery casing 8 and cap 9 are existing devices or equipment, or devices or equipment that can be implemented with existing technology. Their power supply, specific composition and principle are clear to those skilled in the art, so they will not be described in detail.

Claims

1. A laser welding device for lithium battery caps, comprising a base plate (1), characterized in that, An operating table (2) is installed on the top surface of the base plate (1). A guide rail (3) is installed on the top surface of the operating table (2). A support leg (4) is snapped onto the top of the guide rail (3). A welding table (5) is fixedly installed on the top surface of the support leg (4). A welding fixture (6) is provided on the top surface of the welding table (5). A lithium battery module (7) is placed inside the welding fixture (6). A battery casing (8) is stacked inside the lithium battery module (7). A cap (9) is placed on the top surface of the battery casing (8). A laser welding mechanism (10) is provided on the top surface of the base plate (1). The laser welding mechanism (10) includes a Z-axis moving frame (1001), which is movably mounted on the top surface of the base plate (1). A connecting rod (1002) is installed on the inner side of the Z-axis moving frame (1001), and an X-axis moving frame (1003) is installed on the outside of the connecting rod (1002). A Y-axis moving frame (1004) is installed on the outside of the X-axis moving frame (1003). A laser welding head (1005) is installed on one side of the Y-axis moving frame (1004). The laser welding mechanism (10) is configured for laser welding between the battery casing (8) and the cap (9).

2. The lithium battery cap laser welding device according to claim 1, characterized in that, The operating table (2) is equipped with a welding feeding mechanism (12). The welding feeding mechanism (12) includes a base (1201). The base (1201) is fixedly installed on the top surface of the base plate (1). An L-shaped mounting bracket (1202) is fixedly installed on the top surface of the base (1201). A mounting seat (1203) is installed inside the L-shaped mounting bracket (1202). A transmission shaft (1204) is installed inside the mounting seat (1203). A transmission shaft (1205) is provided on one side of the base (1201). The transmission shaft (1204) and the transmission shaft (1205) mesh with each other through bevel gears.

3. The lithium battery cap laser welding device according to claim 2, characterized in that, The other end of the second drive shaft (1205) is equipped with a first drive disc (1206). A first swing arm (1207) is provided on the outside of the first drive disc (1206). A first driven disc (1208) is installed at one end of the first swing arm (1207). A first connecting toothed belt (1209) is sleeved between the first driven disc (1208) and the first drive disc (1206). A second swing arm (1210) is connected to one end of the first swing arm (1207).

4. The lithium battery cap laser welding device according to claim 3, characterized in that, A mounting base two (1214) is installed on one side of the base (1201). A transmission shaft three (1215) is installed inside the mounting base two (1214). One end of the transmission shaft three (1215) meshes with the other end of the transmission shaft one (1204) through a bevel gear. The transmission shaft three (1215) can be driven by a motor. A transmission shaft four (1216) is installed on one side of the base (1201). The other end of the transmission shaft three (1215) meshes with one end of the transmission shaft four (1216) through a bevel gear.

5. The lithium battery cap laser welding device according to claim 4, characterized in that, The other end of the drive shaft four (1216) is equipped with a drive disc two (1217), and a swing arm three (1218) is provided on the outside of the drive disc two (1217). The other end of the swing arm three (1218) is connected to a driven disc two (1220). A connecting toothed belt two (1221) is sleeved between the connecting toothed belt two (1221) and the drive disc two (1217).

6. The lithium battery cap laser welding device according to claim 5, characterized in that, One end of the swing arm three (1218) is connected to the swing arm four (1219). A translation frame (1211) is provided between the active disk one (1206) and the active disk two (1217). The bottom surface and one side surface of the translation frame (1211) are respectively fixedly installed with the protrusion two (1222) and the protrusion one (1212). The other end of the swing arm two (1210) is sleeved on the outer surface of the protrusion one (1212). The other end of the swing arm four (1219) is sleeved on the outer surface of the protrusion two (1222). A through groove (11) is opened on one side surface of the operating table (2). An L-shaped connecting frame (1213) is movably connected inside the through groove (11). One end of the L-shaped connecting frame (1213) is fixedly connected to one side surface of the translation frame (1211). The other end of the L-shaped connecting frame (1213) is fixedly connected to one side surface of the welding table (5).

7. The lithium battery cap laser welding device according to claim 6, characterized in that, The top surface of the operating table (2) is provided with a stress relief mechanism (13). The stress relief mechanism (13) includes two sets of fixed frames (1301). A rotating shaft (1302) is rotatably installed between the two sets of fixed frames (1301). A pulley (1303) is installed on the outer surface of the two rotating shafts (1302). A transmission belt (1304) is sleeved inside the two pulleys (1303). A limit frame (1306) is installed on the outer side of the fixed frame (1301). Two toothed plates (1307) are movably engaged inside the limit frame (1306). The two toothed plates (1307) correspond to the two rotating shafts (1302) respectively. A spring (1309) is fixedly connected between the two toothed plates (1307).

8. The lithium battery cap laser welding device according to claim 7, characterized in that, Half gears (1305) are fixedly installed at both ends of the rotating shaft (1302). The half gears (1305) are located above the fixed frame (1301). A C-shaped frame (1308) is fixedly installed on the top surface of the toothed plate (1307). A box (1310) is provided on one side of the C-shaped frame (1308). A connecting pipe (1311) is fixedly connected to the top surface of the box (1310). A rectangular tube (1312) is fixedly connected to the other end of the connecting pipe (1311). A hollow frame (1313) is fixedly connected to the top surface of the rectangular tube (1312). The hollow frame (1313) is fixedly connected to the top surface of the rectangular tube (1312). The top of the box (313) is fixedly connected to an exhaust bracket (1314). The inside of the box (1310) is movably connected to two snap-fit ​​plates (1316). The side of the box (1310) is fixedly connected to an air inlet pipe (1315). The side surface of the snap-fit ​​plate (1316) is fixedly connected to a connecting block one (1317). The other end of the connecting block one (1317) is fixedly connected to the bottom surface of the C-shaped frame (1308). The bottom surface of the welding table (5) is fixedly connected to a connecting block two (1324). The bottom surface of the connecting block two (1324) is fixedly connected to a limit box (1318).

9. A laser welding device for lithium battery caps according to claim 8, characterized in that, The limiting box (1318) has an internal built-in block (1319), and each internal built-in block (1319) has a snap-fit ​​post (1320) that is movably inserted into it. One end of the limiting box (1318) and the internal built-in block (1319) are both trapezoidal. A spring (1321) is fixedly connected between one side surface of the internal built-in block (1319) and the inner side surface of the limiting box (1318).

10. A method for laser welding a lithium battery cap, the method being applicable to the laser welding apparatus for a lithium battery cap as described in claim 9, characterized in that, Includes the following steps: S1: Place the lithium battery module (7) to be welded into the inside of the welding fixture (6) for clamping and fixing. Then, neatly place the cap (9) on the top surface of the battery shell (8) inside the lithium battery module (7). Drive the welding table (5) towards the laser welding mechanism (10) through the welding feeding mechanism (12). Then, by controlling the operation of the laser welding mechanism (10), weld the battery shell (8) and the cap (9). After the welding is completed, drive the welding table (5) away from the bottom of the laser welding mechanism (10) through the continuous operation of the welding feeding mechanism (12) to realize the material discharge operation. S2: By using the motor and the transmission shaft three (1215) to achieve transmission, when the motor is started and the transmission shaft three (1215) is rotated, the swing arm one (1207) is driven to swing, and the driven disk one (1208) is driven to make a circular motion along the outside of the active disk one (1206) through the connecting toothed belt one (1209), which in turn drives the swing arm two (1210) to swing. The working principle between the active disk two (1217) and the driven disk two (1220) is the same as above, which can drive the welding table (5) to move back and forth on the top surface of the operating table (2) to achieve automatic welding and feeding of the battery shell (8) and the cap (9); S3: When the welding table (5) moves away from the laser welding mechanism (10), the two toothed plates (1307) inside the limit frame (1306) can move in the same direction, driving the C-shaped frame (1308) to move. Thus, under the action of the connecting block (1317), the two snap-fit ​​plates (1316) can move towards each other inside the box (1310), squeezing the air between the two snap-fit ​​plates (1316) and squeezing it into the inside of the connecting tube (1311). Finally, under the action of the connecting tube (1311), the rectangular tube (1312), the hollow frame (1313) and the exhaust frame (1314), the air is blown out towards the welded battery casing (8) and the cap (9), so that the heat of the battery casing (8) and the cap (9) can be dissipated quickly. S4: When the welding table (5) moves in the opposite direction to the laser welding mechanism (10), the built-in block (1319) can move continuously towards the spring (1321) under the action of friction, and the distance between the two locking posts (1320) will increase. Conversely, when the welding table (5) moves away from the laser welding mechanism (10), the built-in block (1319) can move continuously away from the spring (1321), and thus the transmission belt (1304) can be clamped under the shape of the limit box (1318) and the built-in block (1319), driving the pulley (1303) to rotate, thereby realizing that during the feeding welding process, the cap (9) will not be blown away from the outer surface of the battery casing (8).

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