Over the past few decades, crystalline silicon (c-Si) solar cells have dominated the global photovoltaic market with above 90% share. Although the module cost has been reduced in the past tens of years, expensive cost is still a main obstacle for c-Si solar cells to compete over fossil-fuel based energy. At present, commercial c-Si solar cells are typically about 180 µm in thickness, however, the cost of the silicon material alone accounts for up to 40% of total module cost. Therefore, to develop ultrathin c-Si photovoltaics like less than 20 µm becomes an alternative technology roadmap to significantly drive down the costs with the advantage of more cost-effectiveness.
Recently, Wensheng Yan’s group reported highly efficient ultrathin c-Si solar cells, where the Si base thickness is as thin as 16 micrometers and the Si is on a thick conductive metal substrate. In this work, they adopt small pyramids for the front surface texture via the photovoltaic (PV) industry compatible chemical wet-etching method with the advantages of low cost and large-scale texturing. In addition, they use the double-layer passivation to reduce surface recombination and thereby achieve higher conversion efficiency. As a result, the best efficiency of 16.4% was reported. This research result shows a great potential for the PV industrial applications via the technology transferring.
Xinyu Tan, Wensheng Yan*, Yiteng Tu, and Can Deng, “Small pyramidal textured ultrathin crystalline silicon solar cells with double-layer passivation”, Optics Express, 25, 14725 (2017).Go To Optics Express