Lifetime of organic solar cells (OSCs) is much depending on the intrinsic stability of the photoactive layer and its resistance to oxidation process. The encapsulation and the thermal annealing are the known methods to reduce degradation caused due to oxygen ingress which could potentially prolong stability of OSCs. This work is focused on two degradation modes of the photoactive layer: the degradation due to intrinsic material properties and degradation due to oxygen ingress. It is demonstrated that the degradation behaviour of a solar cell can be accurately modelled by using fundamental mathematical equations that describe the aformentioned degradation modes in order to evaluate the lifetime of the solar cells. The case-study of poly[N-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) and (6,6)-Phenyl C₇₁ butyric acid methyl ester (PC₇₁BM) based OSCs has been considered to demonstrate the effectiveness of proposed model for assessing the degradation trends. Our experimental results indicate that temperature annealing has enhanced the stability of OSCs; however, it lowered the efficiency (η) of the OSCs. Further, the numerical results suggest the model of real degradation trends by decaying function with consideration to the possible effects of material deformation (during the burn-in period) and oxidation in photoactive layer of OSCs.

有机太阳能电池（OSC）的寿命在很大程度上取决于光敏层的固有稳定性及其对氧化过程的抵抗力。封装和热退火是减少由氧气进入引起的降解的已知方法，该降解可能会延长OSC的稳定性。这项工作集中在光敏层的两种降解模式上：一种是由于固有材料特性引起的降解，另一种是由于氧气进入引起的降解。已经证明，可以通过使用描述上述退化模式的基本数学方程来精确地建模太阳能电池的退化行为，以便评估太阳能电池的寿命。聚[N-9'-十七烷基-2,7-咔唑-alt-5,5-（4'，7'-二-2-噻吩基-2'，1'，3'-苯并噻二唑）的研究]（PCDTBT）和（6，已考虑使用基于₇₁丁酸甲酯（PC ₇₁ BM）的OSC来证明所提出的模型用于评估降解趋势的有效性。我们的实验结果表明，温度退火增强了OSC的稳定性。但是，它降低了OSC的效率（η）。此外，数值结果表明了考虑到材料变形（在老化期间）和OSCs光敏层中氧化的可能影响，通过衰减函数得出的实际退化趋势模型。