Separate silicon cells from end-of-life bifacial glass photovoltaic modules using continuous lasers

Bifacial photovoltaic (PV) modules have been receiving increasing attention because of the harvesting light from both front and back sides. End-of-Life (EoL) PV modules output grow annually, which are rich in recyclable resources such as silicon and metals. A critical prerequisite for recovery is the separation of the laminate. This study presented a novel and rapid separation strategy by laser (1200 W power, 2000 Hz frequency, 5% duty cycle), achieving complete separation of the silicon cells from the Ethylene Vinyl Acetate (EVA) interlayer. Characterizations analysis showed that the surface morphology of anti-reflection coatings (ARCs) on the silicon cells was damaged. In addition, the content of silicon nitride, main component of ARCs, was decreased. Furthermore, the analysis of EVA verified the cleavages C-O bond, while the cross-linked structure of EVA was not disrupted. Thus, complete separation was driven by ARCs disappearance and the bond cleavage. Life cycle assessment demonstrated that this approach was more environmentally friendly than thermal and chemical methods. It also overcame the drawbacks of product mixing and difficult sorting associated with mechanical methods, enabling simple, rapid separation and easy large-scale automation. This strategy dramatically reduces the energy consumption and provides sustainable pathway for recycling EoL bifacial PV modules.