Influence of Polymer Properties on Potential Induced Degradation of PV-Modules

Solar Cells that are prone to Potential Induced Degradation (PID) have been laminated as one-cell mini modules with various types of back sheet and encapsulation materials. Additionally, water soaking and water permeation properties of the encapsulation and back sheet materials have been tested. It was found that modules containing materials with low barrier and high soaking properties lead to a strong loss in shunt resistance after a short period of time. At the same time, materials with high barrier and low soaking properties protect the cells against electrical degradation under high voltage potentials. Surprisingly, modules containing the TPO-encapsulant showed an increase of shunt resistance during during PID test.