The efficiency was measured on an aperture area of 144 cm2 with the module built on a commercial 6×6 in2 glass substrate, comparable to standard commercial silicon solar cells. The substrate used a transparent conductor that was applied with three consecutive slot die coating processes and a newly developed annealing process. The metal electrode was evaporated onto the top of the module..
Twenty-four cells were series-connected through optimized laser based scribes, leaving 95% of the modules area covered with active material, resulting in a stabilized module efficiency of 13.8%.
Individual reference cells, spin coated and slot die coated, with the same device architecture showed cell performances of 14.5%. This aligns with the measured cell performance on the modules developed by the alliance of leading European material and solar panel makers. This means that only the interconnection area contributes to the observed performance loss from cell-to-module. Ten modules were produced and showed high stabilized module efficiency numbers, indicating the production process is capable of high yields.
A key point is that all the layers can be processed in ambient environment and at temperatures below 120⁰C, apart from the electrodes, avoiding the need for expensive equipment, and the deposition and interconnection technologies can be used with industrial Sheet-to-Sheet and Roll-to-Roll manufacturing. This will allow high volume production of flexible and light-weight PV modules in the future.
“With our newly developed, industry compatible, large area coating and crystallisation processes, we were able to scale-up the active area of our solar cell devices with 3 orders of magnitude without any performance loss,” said Francesco Di Giacomo, senior scientist at Solliance Solar Research. “At the same time, we are in the process of introducing a much more stable material stack into our large area deposition processes. ”
“The challenge is to scale perovskite cells to larger size modules whilst keeping the efficiency high and the costs low at a high yield. The reported result, presented on an aperture area comparable to standard commercial silicon solar cells, shows that Solliance Solar Research, with its in depth know-how on processing of organic PV, CIGS and its vast pilot production infrastructure, is excellently placed to realize this upscaling. This 13.8% efficient perovskite based PV module is another important step in this development. Apart from the fact that we are confident to boost quickly the up-scaled Perovskite based PV module efficiency further above 15% we are also currently making good progress to stabilize the performance of these devices under real life operational conditions,” said Ronn Andriessen, Director at Solliance Solar Research.