Conference Paper from 2016 PVSEC: Compatibility of PV Ribbons and Fluxes with EVA Encapsulant Films Currently the reliability requirements for PV module service life are very high (for 25-30 years of service life) and packaging is the predominant cause of failure in modules. Polymer encapsulants, also known as ‘pottants’, play a key role in protecting the PV cell array modules from environmental effects such as UV radiation, moisture, extreme weather, electric leakage and wind damages. The most common polymer encapsulant in PV industry is ethylene vinyl acetate (EVA). Though EVAs are cheaper and versatile in its usage, they are sensitive to chemicals and other environmental factors. Ribbon and specially, flux manufacturers have to take utmost care in designing their products so that products won’t react with EVA and not suffer from reliability issues such as yellowing, thus affecting efficiency and reduced module life. Considering the flux and polymer encapsulant related compatibility concerns, a detailed study (DOE) was undertaken. The goal of the DOE was to achieve reliable solder joints with reduced yellowing of the PV module by optimizing the solder composition and flux chemistries.