From the cell to the module without any loss of efficiency is one of the main challenges of perovskite photovoltaics. Researchers at the Karlsruhe Institute of Technology (KIT) have now produced perovskite solar modules with almost no scaling losses.
To do this, they combined serial laser interconnection with vacuum processing of all layers of the solar cell. They achieved an efficiency of 18 percent on an area of four square centimetres, a world record to date for vacuum-processed perovskite solar modules.
Scaling losses occur on the one hand because the efficiency decreases with larger areas and dead areas that do not contribute to power generation arise due to the series connection. By vapour deposition of all layers of the solar modules in a vacuum, the influence of both loss mechanisms could be minimized. After combining this process with high-precision structuring and series interconnection (engraving of lines) using a laser, the team was able to produce a large-area perovskite solar module for the first time with almost no scaling losses, an important step from the laboratory to industry.
With the combination of vacuum processing and laser ablation, the researchers at the LTI achieved efficiencies of up to 16.6% on a component area of over 50 square centimeters and even 18% on an area of four square centimeters - a world record for vacuum-processed perovskite solar modules. Further optimizations should help to achieve an efficiency of well over 20 % even on larger surfaces.
