L R AS Published on Sunday 15 March 2020 - n° 313 - Categories:R&D , panels
Where do the cracks in the base sheets come from?
American scientists have been trying to understand the causes of premature cracking of polyamide-based backsheets and how polyamide materials interact with the architecture of solar panels. They discovered several factors
which degrade the bottom leaves. These are subject to cracking and degradation of the inner layers, as these areas tend to become stiffer. In addition, degradation is accelerated by the chemicals that descend from the EVA encapsulant from the solar cells to the backsheets themselves.
They found that degradation of the backsheet is accelerated by chemicals damaging the solar cell encapsulant - ethylene vinyl acetate (EVA) film - falling onto the backsheets.
To confirm this, they used chemical and mechanical tests on samples of solar panel backsheets used in the US, China, Thailand and Italy. Most of them showed clear signs of premature cracking. The backsheet areas most affected by cracking and degradation are the inner layers.
They have shown for the first time that acetic acid significantly accelerates chemical degradation and facilitates cracking of the inner polyamide layer.
PV Magazine of 11 March
