Determination of the degradation constant of bulk heterojunction solar cells by accelerated lifetime measurements

Temperature accelerated lifetime measurements are applied to conjugated polymer based bulk heterojunction solar cells. The short circuit current under white light illumination is monitored over time for different temperatures, ranging from 40 degreesC to 105 degreesC. An Arrhenius type dependence of the degradation constant with temperature is observed and an activation energy E-a of similar to350 meV is derived.