SBIR Phase I: Transparent Conducting Nanofiber Composite Electrodes for High Efficiency Thin Film Tandem Solar Cells

This Small Business Innovation Research (SBIR) Phase I project aims to develop low-cost solution-processed transparent conducting electrodes for tandem solar cell applications. Tandem solar cells can be comprised of two vertically stacked thin film solar cells that are each designed to absorb different regions of the solar spectrum, allowing an efficiency that is higher than a single junction device. Tandem solar cells are a promising technology that is capable of achieving more than 25% power conversion efficiency. However, a highly-efficient top cell that is more than 75% transparent in the near-infrared spectral region is required. Currently, transparent electrodes are primarily made of metal oxides, which strongly absorb in the near-infrared portion of the solar spectrum, significantly reducing the potential tandem power conversion efficiency. In this project, PLANT PV will develop new materials that are highly transparent in the near infrared and can withstand high processing temperatures to lower the cost and improve the overall power conversion efficiency of tandem solar devices. The broader/commercial impact of this project will be the potential to provide a novel transparent conducting electrode that is highly transparent in the near infrared for tandem solar cell applications. Solar energy market is currently one of the fastest growing energy sectors in the world. To compete directly with traditional fossil fuels, the cost per watt of installed solar modules must be further reduced. Thin-film based tandem solar cells have the potential to provide high power conversion efficiency and low cost. The transparent conducting electrodes that is highly transparent in the near infrared combined with highly efficient wide-band gap solar cells is expected to lead the way to low-cost, high-efficiency tandem solar cells.