The aim of this project is to develop an understanding of the relationships between the processing, nanoscale structure and device performance of bulk heterojunction, fullerene-free organic solar cells (OSCs). Optimised processing of OSCs has the potential to offer a low-cost, solution-processible, renewable energy source. We have fabricated fullerene-free OSCs based on a blend of ITIC, a small molecule non-fullerene acceptor and PBDB-T, a recently developed donor polymer, with efficiencies as high as 7.7%. We will build upon this work using SANS, to investigate the dependence of the properties of the phase separated nanoscale domains in non-fullerene photovoltaic blends, on processing factors such as thermal annealing, solvent annealing, casting solvent and blend ratio.