SPLTRAK Abstract Submission
Accelerated Durability Evaluation of Emerging Cell Interconnect Technologies
Fang Li1, Dylan J. Colvin2, Kristopher O. Davis2, Andrew Gabor3, GovindaSamy TamizhMani1
1Photovoltaic Reliability Laboratory, Arizona State University (ASU-PRL) , Mesa, AZ, United States
/2Department of Materials Science and Engineering, University of Central Florida, Orlando, FL, United States
/3BrightSpot Automation LLC, Westford, MA, United States

In the current generation high efficiency photovoltaic modules, many new cell interconnection technologies have been implemented. In this study, we investigate the durability of four different cell interconnect technologies using three long-term accelerated stress tests. The interconnect technologies investigated in this study are: conventional five busbar, tabbed interconnect ribbons (ribbon-tabbed); 12 busbar, soldered wire interconnects (solderedwire); shingled cell interconnects attached with an electrically conductive adhesive (shingled); and laminated wire interconnects with no busbar (laminated wire). The accelerated stress tests implemented in this study are: dynamic mechanical load followed by thermal cycling and humidity freeze (sequence 1); thermal cycling (500 cycles; sequence 2); damp heat (2000 hours; sequence 3). In sequences 1 and 2, all the cell interconnect technologies performed well with a maximum degradation of about 4.5% in the laminated wire technology. In sequence 3, the tabbed ribbon technology experienced the highest degradation of about 12% while the soldered wire technology experienced the lowest degradation of about 4.0%. Overall, the average degradation of both modules in all the three sequences is found to be the lowest for the solder wire technology among thefour investigated technologies assuming the influence of encapsulant and backsheet is identical in all the constructions. The pre- and post- stress characterizations (light IV, dark IV, EL, UVF, IR, spectral reflectance, and colorimetry) revealed potential root causes for the different levels of degradations in different accelerated stress tests.