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Title: Defining Threshold Values of Encapsulant and Backsheet Adhesion for PV Module Reliability

The width-tapered cantilever beam method is used to quantify the debond energy (adhesion) of encapsulant and backsheet structures of 32 modules collected from the field. The collected population of modules contains both those that have remained intact and those with instances of either or both encapsulant and backsheet delamination. From this survey, initial threshold values (an adhesion value above which a module should remain intact throughout its lifetime) for encapsulant and backsheet interfaces are proposed. For encapsulants this value is ~ 160J/m 2 and for backsheets ~ 10J/m 2. Here, it is expected that these values will continue to be refined and evolve as the width-tapered cantilever beam method gets adopted by the PV industry, and that they may aid in the future improvement of accelerated lifetime tests and the development of new, low-cost materials.
ORCiD logo [1] ;  [1] ;  [1] ; ORCiD logo [2] ;  [2]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. Stanford Univ., Stanford, CA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2156-3381
Grant/Contract Number:
Accepted Manuscript
Journal Name:
IEEE Journal of Photovoltaics
Additional Journal Information:
Journal Volume: 7; Journal Issue: 6; Journal ID: ISSN 2156-3381
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
Country of Publication:
United States
14 SOLAR ENERGY; 42 ENGINEERING; adhesive strength; reliability; photovoltaic cells
OSTI Identifier: