SBIR Phase I: Improved Solution Processible Small Organic Molecule Architectures for Lightweight-Flexible Photovoltaics.

This Small Business Innovation Research Phase I project will develop new soluble small molecule (SSM) architectures for organic (plastic) photovoltaic (OPV) technology. SSMs are low-cost plastic semiconductors that can be printed as an ink or spray painted onto conventional plastic sheets to fabricate extremely inexpensive, lightweight, and flexible solar cells. Development of organic solar cells has primarily been based on small molecules deposited from vapor (an expensive and constraining process) or solution-processed polymers; semiconducting polymers by nature are inherently impure and are limited to small batch sizes with inconsistencies between batches. SSM-OPV technology removes these critical development and manufacturing barriers. The overall objective is to further improve the efficiency and lifetime of already highly efficient SSM-OPVs through an approach that is expected to lead to substantially improved isotropy in the optical and electrical properties, which in turn can lead to better charge transport and enhanced efficiency. It is also expected to improve the device lifetimes by reducing degradation over time via crystallization. Therefore this project will be addressing two of the most critical barriers to the commercialization of OPV technology. The broader impact/commercial potential of this project is the promise of very low-cost solar cells that are extremely lightweight and flexible, and which are domestically manufactured via low-cost roll-to-roll processing. These plastic solar cells promise to be substantially lighter and more flexible than existing technologies, with competitive efficiencies and lifetimes for the niche portable solar market. The market for niche solar applications made from lightweight flexible photovoltaics includes stand-alone portable chargers for military and retail users as well as integrated systems including integration with tents, awnings, recreational vehicles, and tensile fabric structures. This market is relatively new and is quickly growing despite the fact the market needs are poorly met by currently available technologies. Currently available photovoltaics in the portable solar market have limited flexibility thereby increasing their collapsed volume and weight. While still new, the niche flexible solar market is predicted to surpass 32 gigawatts (GW) and $58 billion by 2019. The market for OPV stand-alone portable chargers alone is predicted to reach $222 million by 2015. There is also potential that SSM-OPV technology could make inroads into the building integrated PV (BIPV) market or the even the much larger utility scale market.