Accelerated weathering testing principles to estimate the service life of organic PV modules

Although polymer and organic photovoltaic modules represent a promising alternative to technologies based on inorganic semiconductors in terms of versatility and cost, reliable methods to test and improve their long-term stability in end-use environments still need to be developed. To be compatible with product development cycles and time-to-market constraints, the testing should provide data quickly enough to allow for changes in formulation and/or design. Over the last decades, various established large-scale industries have been refining approaches to estimate the service life of polymer-based materials and products. State-of-the-art methodologies rely on outdoor and laboratory accelerated aging techniques that combine factors of stress in a similar way as seen in the end-use environment, though at increased levels. However, testing procedures developed by the organic electronics industry in general and OPV in particular do not systematically apply the basic principles of accelerated testing that would ensure the reproduction of failure modes seen in real life. This paper takes a close look at the crucial components of a comprehensive test program aimed at estimating the long-term durability of OPV products.

Research highlights
► OPV products lifetime affected by combined action of sunlight, moisture, and heat.
► Only way to obtain reliable lifetime estimates is accelerated weathering testing.
► Tools to design sound weathering test programs developed by the plastic industry.
► Acceleration obtained by increasing stress level and time compression, with limitsIn general, the higher the acceleration the lower the relevance