Electrochemical Corrosion within Solar Panels

Abstract

This paper is mainly focusing on electrochemical failure modes for silicon based technology frequently observed in field recently and referred to as so-called ‘snail tracks’. Suitable test sequences are presented for both failure provoking and for risk analysis for field panels already affected. Different field findings - referred to as ‘snail tracks’ - have been categorized with respect to their optical appearance. Relevance for power and yield issues in field has been investigated and correlated to underlying crack issue as well as additional corrosive phenomena. Affected field panels have been further characterized with respect to their isolation properties. Results for leakage current measurements as well as interfacial adhesion (glass/EVA) are presented. Material investigations have been conducted and bulk resistivity for different encapsulation materials (including different EVA types/suppliers) are presented.