Nickel strip is a key material used in the battery manufacturing field to connect the positive and negative electrodes of battery cells with the protection board, and it has various physical states such as soft state, semi-hard state and hard state. The thickness specification of this material is between 0.03 and 1.20mm, the width range is 2 to 150mm, the surface has a silver-white metallic luster, and the density is 8.9g/cm³.
In the manufacturing of lithium batteries, nickel strips are reliably connected to copper tabs through a spot welding process with a current of 100-150KA and a pulse width of 1-3ms. At the same time, they are used as positive electrode TAB assemblies in nickel-metal-hydride batteries.
I. Pre-process Planning
1. Clarify the welding technical parameters: Determine the current range (80-150A) and the diameter of the welding wire (0.8-1.2mm) based on the thickness of the base material and the form of the joint
2. Equipment selection criteria: For batch production, pulse MIG welding machines should be given priority. For small-batch operations, argon arc welding equipment can be used
3. Work environment assessment: Fire blankets and ventilation equipment should be provided within a working radius of 3 meters
Pure nickel strip
Ii. Specifications for Material Pretreatment
1. Surface degreasing treatment: Clean the surface of the base material with acetone until no oil stains remain
2. Bevel processing: Nickel strips with a thickness exceeding 3mm need to be processed with a 30° single-sided V-shaped bevel
3. Storage requirements for welding materials: Nickel-based welding wires should be placed in a constant temperature drying oven (humidity ≤40%).
Iii. Welding Process Control
1. Temperature management: For thick plate welding, preheating to 150-200℃ is required, and the interlayer temperature should be controlled below 100℃
2. Protective gas configuration: A mixed gas of 98%Ar and 2%O2 is adopted, with a flow rate set at 12-15L/min
3. Welding parameter verification: The first piece needs to undergo macroscopic metallographic inspection to confirm that the penetration depth meets the standard
Iv. Key Points of Post-welding Treatment
Weld seam trimming: Use a dedicated nickel strip scraper to remove the oxide layer
2. Non-destructive testing: X-ray flaw detection shall comply with the GB/T 3323-2005 Grade II standard
3. Stress relief: Important structural components need to undergo annealing treatment at 600℃ for 2 hours
Special Safety Operation Tips
- A coated protective face mask (light-blocking number ≥12) must be worn.
Toxic gas alarm devices should be installed in the welding area
Do not touch high-temperature welded parts with bare hands. (Only handle when cooled to below 50℃.)
This process has been successfully applied in high-end manufacturing fields such as inner lining welding of LNG storage tanks and TAB connection of power batteries, and its key technical indicators meet the requirements of ASME BPVC IX standards.
Your message must be between 20-3,000 characters!