The high conversion efficiency of perovskite solar is only restricted to small-sized cells, and reduces once the dimension of cells is enlarged, though German scientists have recently developed a large-sized perovskite solar module that achieves a new record in conversion efficiency at 18%.
The perovskite solar sample that is still inside the laboratory has achieved a conversion efficiency of 25%, and scientists are accelerating on the commercialization of this solar technology that is low cost and easy to produce, though the priority right now is to resolve commercial challenges of perovskite solar, such as the expansion on cell sizes.
Tobias Abzieher, Director of the vacuum-deposited perovskite technology at the Light Technology Institute (LTI), commented that perovskite solar cell is a thin film solar cell that can be formed into large-sized solar modules through a multilayer splicing method, thus structuring lines are also required when drawing the deposited solar energy into various layers of the solar cell so as to connect all cell materials.
The difficulty mentioned above amplifies when cells are enlarged in sizes, where the deposition of solar materials becomes harder in elevation, and the connection of active solar layers would also create dead zones, which are bound to impact the efficiency of solar. The dead zone absorbs the electrons from other areas like a black hole, and annihilates currents and voltages.
The research team at KIT managed to reduce the difficulty of deposition and the impact from the dead zones through vapor deposition, and pointed out that the advantages of vacuum deposition lie on the high degree of controllability and restricted process variables. The research team created a large-sized perovskite module using the laser engraving by integrating the new precision structure with the connection technology, and achieved a scaling loss of almost zero in the particular creation for the first time, which marked an important step for perovskite cells in marching from the laboratory to the industry.
Through vacuum and laser ablation, LTI researchers produced a 50cm2 perovskite solar module that has a conversion efficiency of 16.6%, which elevated to 18% when the module is shrank to 4cm2 that also achieved a new world record. David Ritzer, PhD student at LTI, commented that an increase of more than 500 times in dimension did not generate any losses in efficiency.
Researchers will be focused on the optimization of the solar module design and the further contraction in dead zones in the future. Ulrich W. Paetzold, academic tenure of KIT, commented that a comprehensive utilization of this technology in creating 20% perovskite module and larger modules is attainable in the foreseeable future.
(Cover photo source: KIT)