Understanding PV Polymer Backsheet Degradation through X-ray Scattering
Stephanie L. Moffitt1, Pak Yan Yuen2, Michael Owen-Bellini3, David C. Miller3, Donald Jenket3, Ashley Maes4, James Hartley4, Todd Karin5, Peter Hacke3, Reinhold H. Dauskardt2, Laura T. Schelhas1
1SLAC National Accelerator Laboratory, MENLO PARK, CA, United States
/2Stanford University, Stanford, CA, United States
/3National Renewable Energy Laboratory, Golden, CO, United States
/4Sandia National Laboratory, Albuquerque, NM, United States
/5Lawrence Berkeley National Laboratory, Berkeley, CA, United States

Understanding how photovoltaic (PV) module backsheet polymers age and degrade in the face of environmental stresses is important for designing polymers that can maintain their structural integrity after decades of outdoor exposure. X-ray scattering is a powerful technique for exploring backsheet polymer structure at the Å- (wide angle, WAXS) and nm- (small angle, SAXS) length-scale. Here we present the use of SAXS and WAXS to study pristine and aged polymer backsheets. The structural insight from these techniques can be used to corroborate the degradation induced by accelerated testing with the degradation seen in field-aged PV materials.