End-of-life management of bifacial solar panels using high-voltage fragmentation as pretreatment approach

End-of-life (EOL) solar modules, which are mainly composed of c-Si panels, have gradually become the focus of international attention in parallel with booming solar installation. High-voltage fragmentation (HVF) has been proved to be effective for selective delamination of c-Si panels with backboards. Due to higher photoelectric conversion efficiency, bifacial modules are occupying increasing market share of c-Si panels yet little research about their EOL management is pursued. In this paper, typical bifacial solar panels are dismantled by HVF with different energy input as a way of pretreatment in the whole EOL route. Experimental results testify the feasibility and effectiveness of HVF which can be divided into four stages according to morphology in the process of delamination. Optimal pretreatment is realized after 300 pulses 160 kV with input power to be 192.76J/g, when average particle size is 1.5 mm, about 5% of the initial. Al and Ag are concentrated in fractions of 0.05 mm-2 mm, while Cu, Pb and Sn concentrated in fractions under 0.25 mm which provides great convenience for subsequent extraction. Quantitative size-energy relationship is also obtained by fitting which conforms to fracture theory. Detection results of pollutants in water show that HVF is environment-friendly without secondary pollution. On the basis of experimental results, new closed-loop EOL projection of c-Si solar modules taking HVF as the pretreatment and core technology is worked out ultimately. (C) 2020 Elsevier Ltd. All rights reserved.