Chemical and mechanical interfacial degradation in bifacial glass/glass and glass/transparent backsheet photovoltaic modules

Journal Article · Wed Jun 29 00:00:00 UTC 2022 · Progress in Photovoltaics

DOI: https://doi.org/10.1002/pip.3602 · OSTI ID:1874528

Spinella, Laura  ^[1]; Uličná, Soňa  ^[2]; Sinha, Archana  ^[2]; Sulas‐Kern, Dana B.  ^[1]; Owen‐Bellini, Michael  ^[1]; Johnston, Steve  ^[1]; Schelhas, Laura T.  ^[1]

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1. National Renewable Energy Laboratory Golden CO USA
2. SLAC National Accelerator Laboratory Menlo Park CA USA

Abstract Glass/glass (G/G) photovoltaic modules are quickly rising in popularity, but the durability of modern G/G packaging has not yet been established. In this work, we examine the interfacial degradation modes in G/G and glass/transparent backsheet modules under damp heat (DH) with and without system bias voltage, comparing emerging polyolefin elastomer (POE) and industry‐standard poly(ethylene‐co‐vinyl acetate) (EVA) encapsulants. We investigate the transport of ionic species at cell/encapsulant interfaces, demonstrating that POE limits both sodium and silver ion migration compared with EVA. Changes to the chemical structures of the encapsulants at the cell/encapsulant interfaces demonstrate that both POE and EVA are more susceptible to degradation in modules with a transparent backsheet than in the G/G configuration. Adhesion testing reveals that POE and EVA have comparable critical debond energies after the DH exposures regardless of system bias polarity. The results of this study indicate that the interfacial degradation mechanisms of G/G appear to be similar to those of conventional glass/backsheet modules. For emerging materials, our results demonstrate that POE offers advantages over EVA but that transparent backsheets may accelerate encapsulant degradation due to increased moisture ingress when compared with the G/G structure.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: National Science Foundation (NSF); USDOE; USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
• Grant/Contract Number: AC02-76SF00515; AC36-08GO28308
• OSTI ID: 1874528
• Report Number(s): NREL/JA-5900-83343
• Journal Information: Progress in Photovoltaics, Journal Name: Progress in Photovoltaics Journal Issue: 12 Vol. 30; ISSN 1062-7995
• Publisher: Wiley Blackwell (John Wiley & Sons)Copyright Statement
• Country of Publication: United Kingdom
• Language: English