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Repair of Cracked Backsheets: Long-Term Stability
Y. Voronko, G.C. Eder, W. Mühleisen, L. Neumaier, C. Breitwieser, K. Knöbl, S. Feldbacher, G. Oreski, N. Lenck
Photovoltaic Modules and BoS Components
Subtopic: PV Module Design, Manufacture, Performance and Reliability
Event: 38th European Photovoltaic Solar Energy Conference and Exhibition
Session: 4CO.2.5
ISBN: 3-936338-78-7
0,00 EUR
Document(s): presentation


Polymeric photovoltaic (PV) backsheets are designed to protect the active components of the module (solar cells, electrical connectors) from environmental stress and act as an electrical insulator according to the required safety specifications (IEC 61730-1). Several variations of backsheet compositions are available on the market, mainly laminated multi-layer stacks and co-extruded films. When looking at the reliability of glass/backsheet modules it was noted that the most frequent backsheet failures are cracking, delamination and yellowing [1]. Within the last decade, an enhanced occurrence of backsheet defects was observed in the field after only 4 to 7 years operational time (see figure 1) and reported at several conferences and publications. Premature material degradation of backsheet leads to cracking of diverse severity and can cause a reduction in electrical safety - in worst case electrical insulation failure. Materials cracking was noticed mostly with PA (Polyamide), PVDF (Polyvinylidene Fluoride) and PET (Polyethylene Terephthalate) based backsheets