A Study on the Lifetime Prediction of Organic Photovoltaic Modules under Accelerated Environmental Conditions

In this paper, the correlation between the shelf life of the encapsulated organic photovoltaic (PV) module and different damp heat conditions was investigated by calculating the total amount of water vapor permeated into the organic PV modules. The organic PV module was encapsulated with a commercially available barrier-coated polyethylene terephthalate (PET) substrate by using an optically clear adhesive. The total amount of the permeated water vapor into the module during the damp heat test was calculated by using the finite-element method. Based on simulation results from accelerated damp heat conditions, the lifetime of the module operated at 25 °C/50% relative humidity was predicted. Additionally, it was found that the dominant permeation path of the water vapor into the module is the side edge area and not the barrier-coated PET, based on results from experiment and simulation. Hence, the extension of lifetime for the encapsulated organic PV module was demonstrated by side sealing.