Sumati PV Ribbon is specially engineered for automated high-speed tabber-stringers. Our continuous annealing process guarantees a yield strength under 80 MPa, preventing wafer bowing and micro-cracks in solar cell assembly.
| Base Material | ETP Copper (TU1) ≥ 99.99% Purity |
| Width Range | 0.90 mm – 8.00 mm (± 0.05 mm) |
| Thickness Range | 0.08 mm – 0.50 mm (± 0.005 mm) |
| Yield Strength | < 80 MPa (Ultra-Soft) |
| Elongation | ≥ 25% |
| Solder Alloys | Sn60Pb40, SnAgCu (Lead-Free), SnBi |
Metallurgical excellence engineered for automated tabber-stringer lines, high solar cell yield, and long-term module reliability.
Sumati Photovoltaic Ribbon is precision-manufactured from certified 99.99% pure Electrolytic Tough Pitch (ETP) copper rods (TU1/C11000 grade). Utilizing state-of-the-art multi-stage polycrystalline diamond-die drawing lines and inline continuous induction annealing under a strictly monitored nitrogen-hydrogen protective atmosphere, our interconnect ribbons achieve an ultra-soft yield strength below 80 MPa with elongation exceeding 25–30%.
This exceptionally low yield stress minimizes residual thermal and mechanical tension generated during string soldering. As contemporary photovoltaic cell wafers become progressively thinner (< 130 µm on TOPCon and HJT platforms), Sumati ribbons eliminate silicon wafer bowing, cell warpage, and invisible micro-fissuring, dramatically improving module manufacturing yield rates across high-speed tabber-stringers.
Our proprietary continuous hot-dip tinning process submerges the copper core through molten solder baths with ultrasonic fluxing, creating a concentric, metallurgical intermetallic bond (Cu6Sn5/Cu3Sn) controlled within 1.0 µm thickness. This avoids brittle intermetallic growth that causes joint detachment after years of field thermal cycling, ensuring 25 to 30 years of uninterrupted solar performance.
We formulate specialized solder alloys tailored to client stringer temperatures, ranging from standard eutectic leaded alloys (Sn60Pb40 / Sn63Pb37) to ultra-clean, lead-free compositions (Sn96.5Ag3.0Cu0.5 and low-temperature bismuth alloys) fully compliant with international RoHS, REACH, and IEC 61215/61730 reliability standards.
