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

This Small Business Innovation Research (SBIR) Phase II project will develop new soluble small molecules (SSM) and device 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. In this project we will further increase the power conversion efficiency (PCE) of our SSM-OPV cells by developing SSM-OPV tandem cells, which will increase the theoretical PCE limit as well as directly improve the actual PCE. Unlike conventional solar where the fabrication of multi-junction solar cells is complex and cost is prohibitively high, SSM-OPV is well suited for low cost tandem cell fabrication. Therefore this project will be addressing one 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 and PV integrated roofing. 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 membrane roofing. 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/portable solar market is predicted to surpass 420MW and reach $600 million by 2020. The market for flexible building-integrated PV (BIPV) roofing products is projected to reach $3 billion by 2018. There is also potential that SSM-OPV technology could make inroads into the much larger utility scale market in the future.