Remanufacturing Perovskite Solar Cells and Modules–A Holistic Case Study

Abstract

While perovskite photovoltaic (PV) devices are on the verge of commercialization, promising methods to recycle or remanufacture fully encapsulated perovskite solar cells (PSCs) and modules are still missing. Through a detailed life-cycle assessment shown in this work, we identify that the majority of the greenhouse gas emissions can be reduced by re-using the glass substrate and parts of the PV cells. Based on these analytical findings, we develop a novel thermally assisted mechanochemical approach to remove the encapsulants, the electrode, and the perovskite absorber, allowing reuse of most of the device constituents for remanufacturing PSCs, which recovered nearly 90% of their initial performance. Notably, this is the first experimental demonstration of remanufacturing PSCs with an encapsulant and an edge-seal, which are necessary for commercial perovskite solar modules. This approach distinguishes itself from the "traditional" recycling methods previously demonstrated in perovskite literature by allowing direct reuse of bulk materials with high environmental impact. Thus, such a remanufacturing strategy becomes even more favorable than recycling, and it allows us to save up to 33% of the module's global warming potential. Remarkably, this process most likely can be universally applied to other PSC architectures, particularly n-i-p-based architectures that rely on inorganic metal oxide layers deposited on glass substrates. Finally, we demonstrate that the CO 2 -footprint of these remanufactured devices can become less than 30 g/kWh, which is the value for state-of-the-art c-Si PV modules, and can even reach 15 g/kWh assuming a similar lifetime.

Remanufacturing of perovskite solar cells

“…Chen et al showcased material recovery through delamination of epoxy-encapsulated devices following thermal treatment at 250 °C for 2 minutes, 43 while Bogachuk et al employed mechanically assisted thermal delamination at 120–140 °C for modules encapsulated with thermoplastic olefins (TPO) and polyisobutylene (PIB)-based edge seal. 66 These examples underscore the varying energy requirements and methodologies associated with delamination, contingent upon the sealing methods and materials used. More research is required to identify materials and methods that are not only effective for encapsulation and lead capture but also energy-efficient in application, constituted by abundant and inexpensive materials and are conducive with EoL processes.…”

“…In remanufacturing methods requiring the removal of layers atop the perovskite, the absence of spiro-MeOTAD presents an advantage, as the carbon layer is comparatively inexpensive. Bogachuk et al 66 recently reported a remanufacturing technique for encapsulated triple-mesoscopic carbon-PSCs with a 1.5 cm 2 active area, and assessed potential carbon footprints for 1 m 2 remanufactured modules. The proposed method involves thermally-assisted mechanical separation and acetone immersion to remove sealant and encapsulant, while methylamine and ethanol baths are used to remove the carbon layer and the degraded perovskite.…”

“…A 33% reduction in GWP was estimated for optimised remanufactured modules, and a decrease of the “break-even” lifetime from 16 years to 10.7 years. 66…”