PID 的介绍: Potential-induced degradation (PID) of crystalline silicon solar cells was first observed by Sunpower in 2005. It was found that leakage current through the front glass and encapsulation material leads to accumulation of trapped negative charge on at the surface of the cells. The surface passivation provided by the front surface field of these cells degraded. The fill factor (FF), short-circuit current density (Jsc) and open-circuit voltage (Voc) were significantly reduced.
In 2010, NREL and Solon demonstrated that PID is a fundamental risk whenever state-of-the-art p-typecrystalline silicon solar cells are used in standard modules at high negative bias.
Ionic motion in the packaging of the active layer leads to accumulation of charge or charged ionsover the semiconductor surface Charge influences surface field of semiconductor active layer. In severecases, accumulation of mobile ions such as Na in the glass leads to delamination.
Ionic motion also takes place within the active layer, degrading semiconductor junction propertiesand causing shunts.
Usually in the presence of humidity in the packaging, electrolytic corrosion occurs and macroscopictransport of ionized conductor metal is observed.