Understanding the Snail Trail Effect in Silicon Solar Modules on Microstructural Scale
Year: 2012
Type: article
Abstract: Crystalline silicon solar modules at outdoor exposure may show the so called snail trail effect, which appears as brownish discolored contact fingers on cell edges and/or micro cracks. In the study presented here we investigated silicon solar modules with snail trails on microstructural scale to clear up their chemical and structural properties. For this purpose a TEM lamella was prepared by the FIB technique on discolored EVA which was in contact before with a discolored contact finger. To analyze the chemical components of the discolored EVA, EDX mappings and ToF-SIMS measurements on discolored and reference EVA were performed. Cross sections at the Ag contact finger prepared by FIB provide an insight into microstructural details. It turns out, that the snail trail effect is correlated with Ag containing particle clusters which diffuse and agglomerate through the EVA polymer. Further chemical components probably being involved in the chemical reactions were identified.
Source: EU PVSEC
Authors: Richter, S., Werner, M., Swatek, S., Hagendorf, C.
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W43404167