WCA September 2016

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Wire & Cable ASIA – September/October 2016
Technologynews
THE photovoltaic industry has been going through a rapid change
over the last decade. In addition to growth, the industry has
continued to witness relentless price pressures along the PV value
chain. The same is the case in the PV ribbon industry. Only PV
ribbon producers that kept consistent product quality whilst
maintaining low cost base and efficient production process have
remained competitive.
Plasma-based annealing and tinning process represents an
efficient PV ribbon production solution that will ensure consistent,
top quality finished products at low cost.
Plasmait from Austria has introduced a new PV ribbon annealing
and tinning line designed for high output production. The new line
features a maximum production speed of 210m/min. This allows
the line to produce up to 250 tonnes of PV ribbon per annum in a
typical production split between interconnect and bus bar
ribbons.
PV ribbon lines can produce a wide range of interconnect ribbons
and bus bars in a typical size range of 0.8 to 8mm wide and 0.1 to
0.5mm thick. The ribbons are usually coated with 20 micron thick
layer of solder with a coating thickness tolerance of ±3 microns.
The new line can produce ribbons of various yield strength,
typically with Rp0,2% between 50MPa and 90MPa.
Copper ribbons are paid off from a 500kg spool with finished
tinned PV ribbon being spooled onto 4-10kg spools in a
continuous production. The single-head, precision layer winding
spooler includes an accumulator to ensure uninterrupted
production during spool changeovers on the takeup side. Some
producers choose to equip the line with an automatic spool
changeover unit that can be integrated with the takeup unit.
Multiple lines can therefore be operated with a single operator,
which reduces labour cost.
The PV ribbon line can also be integrated with an in-line rolling
mill to produce interconnect ribbons directly from round copper
wire. A single- or double-stand rolling mill can be used for in-line
operation subject to required size and tolerance of the finished
ribbon.
Unlike traditional tinning processes, plasma tinning lines operate
without chemical cleaning and fluxing whilst rolling runs without
cooling agents. This makes the whole production dry and
environmentally friendly.
Flux-free plasma tinning process avoids contamination of tin bath
with flux, which makes a big difference in the cost of tin waste.
Average annual savings in terms of tin waste alone is as high as
€100,000 per line when compared to the traditional flux-based
tinning process. This does not take into account the savings a PV
ribbon producer yields from reduced scrap rates.
The new line allows PV ribbon producers to reduce labour costs
and scrap rates whilst improving production consistency and
product quality. It also features low energy use and maintenance
cost per kg of finished material. This combined allows the new PV
ribbon line to claim the lowest cost of PV ribbon production
overall, according to Plasmait.
Plasmait GmbH – Austria
Website:
New PV ribbon and
tinning line