A Defect Formation as Snail Trails in Photovoltaic Modules

Han-Chang Liu, Chung-Teng Huang, Wen-Kuei Lee, Shih-Siang Yan, Fu-Ming Lin

Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan.

DOI: 10.4236/epe.2015.78032                

Abstract

In this paper, we discussed the field failures of the brownish discolored lines like snail trails in PV modules. We were successful simulation snail trails in laboratory and outdoor field. We had found out some types EVA (ethylene vinyl acetate) encapsulants and back sheets which had the serious snail trails but others were snail trails free. Furthermore, according to IEC 61215 accelerated aging testing, we also found only within 2% power loss after these modules impacted by snail trails. The main power losses over 5% were come from cell micro cracks before snail trail formation. That snail trails occurrence means solar cells should have micro cracks. In here, we contributed the snail trail effects and avoided the failures in future photovoltaic modules performance.

Keywords

Snail Trails, Micro Crack, EVA (Ethylene Vinyl Acetate)

Conflicts of Interest

The authors declare no conflicts of interest.

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