Meaning
Non-contact joining technique using focused laser radiation to fuse battery cell current collector tabs to interconnect busbars forms low-resistance electrical connections in pack assembly. In automated manufacturing, cell tab laser welding provides high-speed joining with minimal heat input, preventing thermal damage to internal cell separator membranes. Boundary limits apply to tab material thickness, reflectivity, and surface cleanliness prior to beam exposure.
Weld integrity directly dictates long-term electrical conductivity.
Process Control
Optical monitoring systems track beam focus, weld pool infrared emissions, and back-reflection to verify joint quality in real time. Automated lines using cell tab laser welding adjust laser power and pulse duration to compensate for minor gap variations between tabs. Beam shaping minimizes spatter and micro-cracking.
Metallurgical Quality
Fusion zone metallurgy determines joint mechanical strength and electrical contact resistance between copper and aluminum tab layers. Microstructural analysis of cell tab laser welding verifies sufficient penetration depth without piercing protective cell sealing gaskets. Defect-free welds prevent resistance heating during high-current discharges.
Quality Inspection
Online process metrics and post-weld optical coherence tomography detect voids, porosity, and incomplete penetration immediately after joining. Quality control teams review cell tab laser welding records to isolate defective modules before electrical potting operations. Mechanical peel testing validates weld shear strength.
