PV Ribbon Properties for Superior Solar Module Manufacturing and Performance

When selecting a supplier for your PV Ribbon, it’s important to know they understand the critical material requirements for superior module performance.  Every Ulbrich Solar PV Ribbon is engineered to meet the customer’s unique design requirements. There are many critical factors involved in engineering and manufacturing PV Ribbon. Six of these factors are discussed below.

1)      Base Material.  Copper is commonly used as the base material for PV Ribbon.  Common alloys include: CDA 102 made to ASTM B170, CDA 110 to ASTM B5, ETP1 to DIN EN 13602, and Cu-OF1 to DIN EN 13602.  Ulbrich Solar typically produces interconnect wire with CDA 102 and buss wire with CDA 110 or better.

In addition to copper, Ulbrich is now offering several aluminum alloys as a base metal including, but not limited to: 1050, 1350, 1188, and 1199.  The type of metal you select directly affects its conductivity and, as a result, the power output of the module.

2)      Solder Coating.  Solder composition and coating thickness are important parameters which affect the strength and reliability of the solder bond.  The coating thickness is selected to match a customer’s interconnect process. Ulbrich Solar can produce the Solder Coating required to meet a customer’s bonding requirements.

3)      Yield Strength.  Low Yield Strength interconnect wire minimizes solar cell breakage by reducing the stress on the cell during the stringing process.  Copper expands at a different rate than silicon during heating and cooling, thus creating stress at the bond. Further, module manufacturers are incorporating thinner solar cells to enhance performance and reduce costs.  Ulbrich Solar has the ability to produce low Yield Strength ribbon to reduce cell breakage while optimizing the ribbon cross-section, thus maximizing module power.

4)      Elongation.  Elongation is a measure of the wire’s ductility.  High Elongation wire, which means high ductility, enhances the long-term module reliability.  High Elongation wire is better able to withstand the punishment of temperature cycling in the field.  Ulbrich Solar can produce the wire with high Elongation and low Yield Strength for a longer module life with the lowest cell breakage.

5)      Camber.  Camber is a measure of the wire’s straightness.  Interconnect and buss wire must be straight with minimal camber.  Camber can be difficult to control when producing wire with low Yield Strength.  If Camber is not controlled, a module manufacturer can experience problems during the stringing process, such as missed bonds.  Ulbrich Solar controls the rolling process, coating thickness, and winding parameters to minimize Camber.

6)      Winding.  Winding is an important factor to optimize the payoff of the wire.  The spool size, wire tension, and wind parameters must be strictly controlled to minimize Camber, eliminate tangle, and preserve Yield Strength.  Ulbrich Solar carefully monitors the winding process to meet a customer’s needs. In addition, our spools are packaged with corrosion inhibitor wraps (paper or stretch-wrap).  Spools can also be vacuum-packed. Depending on the wire size and application, Ulbrich Solar can also wind the wire onto pancake cores for the optimal payoff.

Ulbrich Solar’s PV Ribbon is manufactured to SEMI Standard PV18-0811 and tested to SEMI Standard PV19-0811.  For more information on Ulbrich Solar Technologies and our family of PV Ribbon products, contact us at:


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