Low-Stress Silicone Encapsulant for PV Inverters

As the total cost of non-active materials in solar systems outstrips that of photovoltaic (PV) modules, solar manufacturers are seeking new, high-performing materials able to drive down balance-of-system costs while increasing the efficiency and durability of their products. Against this competitive backdrop, Dow Corning introduced Dow Corning® EE-3200 Low-Stress Silicone Encapsulant – the latest addition to its broad and growing portfolio of advanced solutions designed to expand performance and durability of solar micro-inverters, power optimizers and other high-value components.

“EE-3200 Low-Stress Silicone Encapsulant exemplifies the materials innovation needed to drive down solar inverter system costs, enhance overall performance and help solar technology become ever more competitive with traditional energy sources,” said Geoff Gardner, global strategic marketer for Electronics at Dow Corning. “Together with our broad portfolio of solar encapsulants, coatings, adhesives, frame sealants and thermal interface materials, this advanced new silicone encapsulant further expands the competitive benefits Dow Corning offers solar customers along a wide segment of the industry’s value chain.”

Offering a tailored balance of low viscosity, room-temperature cure, low hardness and good thermal conductivity, EE-3200 Low-Stress Silicone Encapsulant is a two-part silicone formulation that helps minimize processing costs compared to competitive polyurethane encapsulant materials. Unlike polyurethanes, which often require pre-heating before application, Dow Corning’s advanced silicone formulation eliminates the pre-heating step – with its associated costs – and enables electronic assemblies to be filled more quickly. Additionally, where polyurethane encapsulants generally take 90 minutes to cure, EE-3200 Low-Stress Silicone Encapsulant offers simple room-temperature cure with the option to reduce cure time to 20 minutes at temperatures of 50 degrees C, further minimizing processing costs.

Dow Corning’s advanced low-stress encapsulant protects sensitive electronic components against mechanical strain caused by thermal cycling while also providing mechanical adhesion to prevent corrosion from moisture ingress. This improves the reliability, durability, and therefore the value of solar micro-inverters. The components in electronic modules encapsulated with EE-3200 Low-Stress Silicone Encapsulant were exposed to 60 percent less stress in accelerated aging tests, compared to components in modules encapsulated with polyurethane. This indicates that Dow Corning’s new material can help extend the lifetime of solar installations even under harsh conditions. Its dielectric properties and low viscosity also make it ideally suited for use in today’s smaller designs where traditional encapsulants can entrap voids or experience property changes with exposure to humidity.

“As the leading innovator of silicone-based materials for more than 70 years, Dow Corning is committed to pioneering solar solutions and collaborating with global customers to enable them to provide products that are more reliable, durable and cost competitive”, said Alan Gu, global segment leader for Industrial and Energy Markets at Dow Corning. “Our advanced silicone solar solutions are quickly emerging as the material of choice for today’s solar manufacturers innovating next-generation inverter components for a more sustainable future.”