Laser Welding Revolution in Power Battery Manufacturing: From Cell to PACK Integration

Amid the explosive growth of new energy vehicles, laser welding has become the "gold standard" for power battery manufacturing with its 30% deeper penetration and 50% less thermal deformation compared to traditional processes.

Ⅰ. Mid-section Cell Assembly Revolution

Laser welding penetrates four critical nodes:

1. Can Sealing: Fiber lasers achieve 0.1mm-level seams with hermeticity ≤10⁻¹¹ Pa·m³/s

2. Cap Welding: Vision positioning ensures ±0.05mm precision, yield rate reaches 99.8%

3. Filling Port Sealing: Pulse laser controls heat input <50J/cm², preventing electrolyte contamination

4. Ultra-thin Tab Welding: Beam oscillation technology solves brittle phase issues for 0.2mm Cu-Al dissimilar materials

Case: CATL's 5-series battery line uses blue lasers (450nm) to increase copper absorption by 60% at 120mm/s welding speed

Ⅱ. PACK Module Integration Breakthroughs

Three key advancements in module stage:

1. Multi-material Connector Welding

• Cu-Al joints with hybrid welding (Laser+MIG) achieve tensile strength >120MPa

• Busbar deformation <0.1°

2. Precision Bursting Disc Welding

• 0.3+0.3mm Al sheets welding

• Burst pressure stabilized at 1.5±0.2MPa (meets GB 38031-2020)

3. CTP/Blade Battery Integration

• Beam shaping enables 8:1 aspect ratio for 8-layer foil penetration

Ⅲ. Techno-economic Advantages

Forecast: With 3μm beam shaping optics and AI weld monitoring, laser welding penetration in battery manufacturing will exceed 85% by 2025 (2023: 62%). For more further information, pls click here.