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

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.

Authors:

Spinella, Laura  ^[1];

• Search DOE PAGES for author "Spinella, Laura"
• Search DOE PAGES for ORCID "0000-0003-4905-0626"

Uličná, Soňa  ^[2];

• Search DOE PAGES for author "Uličná, Soňa"
• Search DOE PAGES for ORCID "0000-0001-5287-7179"

Sinha, Archana  ^[2];

• Search DOE PAGES for author "Sinha, Archana"
• Search DOE PAGES for ORCID "0000-0001-5272-1123"

Sulas‐Kern, Dana B.  ^[1];

• Search DOE PAGES for author "Sulas‐Kern, Dana B."
• Search DOE PAGES for ORCID "0000-0003-0814-8723"

Owen‐Bellini, Michael  ^[1];

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• Search DOE PAGES for ORCID "0000-0002-4551-8124"

Johnston, Steve  ^[1];

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• Search DOE PAGES for ORCID "0000-0003-3308-8267"

Schelhas, Laura T.  ^[1]

• Search DOE PAGES for author "Schelhas, Laura T."
• Search DOE PAGES for ORCID "0000-0003-2299-1864"

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+ Show Author Affiliations

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

Publication Date:

Wed Jun 29 00:00:00 EDT 2022

Research Org.:

National Renewable Energy Laboratory (NREL), Golden, CO (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)

Sponsoring Org.:

USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office; National Science Foundation (NSF)

OSTI Identifier:

1874528

Alternate Identifier(s):

OSTI ID: 1876872; OSTI ID: 1888573; OSTI ID: 1897333

Report Number(s):

NREL/JA-5900-83343
Journal ID: ISSN 1062-7995

Grant/Contract Number:  

AC36-08GO28308; AC02-76SF00515; ECCS-2026822

Resource Type:

Published Article

Journal Name:

Progress in Photovoltaics

Additional Journal Information:

Journal Name: Progress in Photovoltaics Journal Volume: 30 Journal Issue: 12; Journal ID: ISSN 1062-7995

Publisher:

Wiley Blackwell (John Wiley & Sons)

Country of Publication:

United Kingdom

Language:

English

Subject:

14 SOLAR ENERGY; bifacial solar; glass photovoltaic modules; photovoltaic; rear-side illumination; transparent backsheet photovoltaic modules; adhesion; bifacial; DuraMAT; EVA; glass–glass; ion migration; POE