The geometrical fill factor of more than 95% for this size of module demonstrates the potential of scaling up this thin-film PV technology from cell to module level. The breakthrough realizes a marketable, thin-film model for applications such as building integrated photovoltaics (BIPV), says the research centre.

Organometal halide perovskites have shown high conversion efficiencies at cell level, making them an “excellent material for thin-film solar cells”. While the power conversion efficiency of this new class of thin film solar cells has increased rapidly in the last few years, further improvements are still needed to make thin-film photovoltaics an attractive technology for industrial production. Larger area processing and narrow interconnections are prerequisites for processing efficient thin-film modules.

“Not only is imec improving the perovskite material, but it is also adjusting the cell and module structure to enhance the conversion efficiency of perovskite solar cells and modules by more than 20%,” said Tom Aernouts, R&D manager for thin-film photovoltaics at imec. “The rapid progress that we are making is based on our strong background and track record in traditional organic photovoltaics.”

Imec develops a platform for glass-based perovskite modules and collaborates with the Dutch joint thin-film PV research initiative Solliance to develop foil-based processes. The high power conversion efficiency and standalone integration in building elements mean that both glass-based and thin-film perovskite PV technology are important technologies for the BIPV market. Imec is working to further increase the conversion efficiency of silicon solar cells by creating a stack with a perovskite cell on top of a silicon solar cell. The perovskite cell will capture the light which is not absorbed by silicon, enabling conversion efficiencies of more than 30%.