Transient Analysis of Ion-Migration Current for Degradation Diagnostics of Perovskite Solar Cells

In this article, we present the degradation diagnostics of perovskite solar cells using transient ion-migration current measurements. It was found that a slow ion-migration current increased after illumination and decreased under dark conditions, indicating that the light-induced reversible change is partly caused by slow mobile ions. In addition, a fast ion migration current was modified after illumination and dark cycles and increased in the dark. Moreover, an increase in the mobile ion concentration can cause an irreversible power degradation and affects power extraction using maximum-power-point tracking. Our findings provide a simple and nondestructive diagnostic of ion-migration-induced degradation in perovskite solar cells.