Let’s Not R-EPE-at Our Mistakes

DuraMAT 2.0

Disruptive Acceleration Science

Category: Encapuslants and Barriers

Recipient NREL (PI: Palmiotti, Elizabeth)

Subs SNL, Dow Inc.

Status Awarded

Abstract EVA/POE/EVA (EPE) co-extruded encapsulants are an emerging “best of both worlds” approach, where EPE is a compromise between the low cost and good adhesion properties of EVA-based encapsulants and the PID resistance of POE-based encapsulants. Despite widespread and rapid deployment, EPE does not have sufficient reliability testing or fielding history to understand risks and degradation modes. The majority of risks associated with EPE integration into modules are anticipated to be adhesion and delamination issues which can enable serious degradation mechanisms and/or safety concerns. In this proposal, we will investigate and model how EPE encapsulants and their associated additives behave under different lamination and environmental conditions to better understand these adhesion issues. Additionally, we will investigate the extent of PID and acetic acid formation of this encapsulant. This project will answer four major questions about EPE: (1) Are differences in lamination behavior and kinetics resulting in adhesion issues? (2) Are differences in material properties resulting in adhesion issues? (3) Are differences in additive migration resulting in adhesion issues? (4) Is EPE truly the “best of both worlds”?