Laser welding for lithium battery busbar FPCs is a cutting-edge technology that is making strides in the battery manufacturing industry. This process utilizes a high-intensity laser beam to join the busbars and FPCs together. The resulting welds are strong and durable, with superior conductivity and minimal heat input.

Peralatan proses dan kerja aliran

Work process: Manually position the FPC board in the module flow to the welding position, take CCD photos for positioning, measure the height with a rangefinder, adjust the focal length of the vibrating lens Z-axis, and weld the aluminum strip and FPC nickel sheet. After welding is completed, cycle in sequence.

1) Process: Weld the nickel sheets of the module

2) Action process: The battery module is carried by the tooling board and moves to the welding station on the double speed line through the double speed chain.

1) Laser head motion system (three-axis):

a) Speed 250mm/s b) Repetitive positioning accuracy ± 0.1mm.

2) Laser welding system

a) Laser wavelength: 1070mm b) Laser power: 350W c) Overall power consumption: 16.5KW

3) Dust collection system

a) Motor power: 380V/50Hz/3kw b) Air volume 210m ³/ H c) Wind speed 8-10m/s

4) Water cooling system

a) Refrigeration capacity: 15L/Min b) Power consumption of chiller: 6KW

5) Laser source - IPG-1KW

6) Laser welding equipment: equipped with automatic ranging, capturing welding trajectory, and autofocus functions, including automatic compensation for 5mm deviation of the automatic intelligent camera and automatic detection of ranging.

7) During welding, nitrogen protection is provided, and there is no burning phenomenon after welding. Nitrogen is provided by Party A (purity 99.99%), and the welding equipment has a connecting pipe and a blowing control device. At the same time, high-pressure components are selected for the nitrogen delivery pipe and solenoid valve (note: welding can also be done without nitrogen).

8) The welding machine is equipped with a nitrogen pressure flow detection device. When the nitrogen is not turned on and the gas volume is below the set value, the welding machine will alarm and pause, and welding will not be carried out (note: welding can also be done without nitrogen).

9) Install a pressure detection device at the blowing port of the vibrating lens. When the blowing pressure is lower than the set value during welding, an alarm will be triggered and welding will not be carried out.

10) The welding machine is equipped with an automatic barcode scanner, industrial control computer, and upper computer software. By scanning the code, the module barcode is bound to the corresponding welding parameters (welding time, power, speed, servo parameters, etc.), and the bound data is saved locally and uploaded to MES.

11) Appearance requirements: a. There is no obvious scratch welding effect after welding. b. There is no obvious color after welding (no nitrogen will affect the appearance).

12) The tensile and shear forces after welding must meet the process requirements, with a tensile force requirement of Greater than or equal to 40N (nickel sheet thickness of 0.3mm, material: nickel); According to the actual situation, adjustments can be made or customers can provide samples for validation data first.

13) Equipped with smoke exhaust and dust removal equipment, effectively removing smoke and dust from welding machines; There should be no obvious smoke residue within 2 seconds after welding a weld seam.

14) The welding machine should have a feedback monitoring function. When the power of the welding machine is different from the set value during welding, an alarm feedback should be triggered.

15) During fiber optic welding, there is no bending damage to the fiber, and the fiber length is over 10M.

16) The shape and size of nickel plate welding can be adjusted.

17) The filter element of smoke exhaust and dust removal equipment should be flame retardant, explosion-proof, and anti-static to prevent the equipment from catching fire and the filter element from catching fire.

18) The electrical box of the welding machine is protected and isolated from the industrial control computer and related instruments, which means it is installed in a place where welding dust does not affect it. Welding dust should not cause frequent adhesion of welding dust between the electrical box, industrial control computer and related instruments.

19) The optimal ambient temperature for the equipment is 10 degree to 35 degree , with a relative humidity of less than 50% (it is recommended to place the laser in an air-conditioned room).

20) The equipment is equipped with a pressure mechanism, and before welding, the nickel sheet needs to be flattened with the busbar, and the bonding surface should be completely adhered.

21) The welding fixture has the function of automatic cleaning of welding slag.

22) Upload welding power, defocus, and protection nitrogen flow data to MES.

23) Effective weld length: Greater than or equal to 3.5 mm.

24) Weld width: 1.5-2.5 mm.

25) Welding shear force: Greater than or equal to 80 N.

26) Welding tension: Greater than or equal to 50 N.

27) Residual width of weld seam on the busbar: Greater than or equal to 1.2 mm.

28) Residual length of weld seam on the busbar: Greater than or equal to 2.5mm.

29) Welding slag quantity: Less than or equal to 2 PCS (single welding slag diameter Less than or equal to 0.3 mm).

30) Meet the requirements for process data collection.

31) Meet the general requirements standards for MES systems.

32) MES system for recording first inspection data.