二軸負荷下におけるフレキシブル太陽電池に生じる損傷のAEモニタリング

抄録

Microdamage initiation and accumulation processes in flexible solar cells under biaxial tensile loading were monitored by acoustic emission (AE) technique. Furthermore, the contribution to the degradation of power generation performance was evaluated using lock-in thermography (LT). Comparing the results of uniaxial with biaxial tensile tests, it was shown that the strains at the onset of the degradation in the maximum power P_max and the short circuit current I_sc were equivalent for both tests. Whereas the open circuit voltage V_oc decreased at lower strain in the biaxial test than the uniaxial. Furthermore, it was also observed that the cracks near the current collection holes were perpendicular to the tensile direction in the uniaxial, whereas in the biaxial, the cracks were radial from the current collection holes. Consequently, the fundamental knowledge on the characterization of durability of flexible solar cells, such as the prediction of degradation was obtained.