Belgian micro and nano-electronics research center Imec of Leuven has reported 11.3 percent aperture area efficiency and 11.9 percent active area efficiency for its perovskite thin-film photovoltaic (TFPV) module. It is a record for this variety of modules, the center reports.
Perovskite promises to be a cheaper alternative to silicon-based solar cells. Researchers have found organometal halide perovskites to be excellent material for thin-film solar cells. And over the past few years thin film solar cells have shown increasingly higher power conversion efficiency.
However, commercial production of modules based on the material has not been possible, primarily owing to the effects of humidity and moisture on this naturally occurring mineral.
Also, larger-area processing and narrow interconnections are prerequisites for processing efficient thin-film modules.
Imec measured the efficiency of its photovoltaic module over an aperture of 16 square centimeters with geometrical fill factor of more than 95 percent.
According to a statement, Imec used conventional lab-scale spin coating process to fabricate the higher efficiency cells.
The center also used linear coating technique (blade coating) for all solution-based layers to prove the industrial viability of the fabrication methods.
It found the aperture area efficiency of the modules thus produced to be 9 percent. The center believes the development can help bring thin-film solar technology to industrial scalability for applications such as building-integrated photovoltaics (BIPV).
Tom Aernouts, manager of research and development of thin-film photovoltaics at Imec says the center was aiming at conversion efficiencies of more than 20 percent for this type of thin-film solar cells.
Also, Imec is developing a platform for glass-based perovskite modules and is collaborating with Dutch-German-Flemish thin-film PV research initiative Solliance. ECN, Imec, TNO, Holst Centre, TU/e, Forschungszentrum Jülich, University Hasselt and Delft University of Technology are partners in Solliance.
Imec is also exploring possibilities of perovskite-silicon combination modules by stacking one on top of the other. The idea is that perovskite cell will capture light that is not absorbed by silicon cells, enabling conversion efficiencies of more than 30 percent.
Ajith Kumar S