German adhesives and sealants producer Wevo-Chemie has developed thermally conductive potting compounds and gap fillers that target heat removal and ensure component mechanical stability in EV power electronics.

The epoxy resin- and silicone-based materials protect against electrochemical corrosion and provide reliable electrical insulation due to their low ion content. Wevo has optimized the flow properties of these potting compounds to fill small gaps despite their high thermal conductivity and filler content. By adjusting the glass transition temperature and using special fillers, materials can be made to withstand –40° C to +180° C inverter temperatures, preventing cracking during thermal shocks, cycles and damp-heat storage. 

Wevo has optimized the adhesion of the silicones to metals such as aluminum, so that the potting compounds can be used in the area around the component housing or for components such as coils or printed circuit boards (PCBs). The materials can be optimized for specific applications, making them suitable for electronic control units (ECUs) and DC/DC converters.

“If full encapsulation of the inverter is not possible or not desirable, a local connection can be established to the component housing or the cooling system using gap fillers developed by Wevo,” the company said.

Source: Wevo-Chemie