EMI/RFI conductive silicones for EV sealing and shielding

Ballston Spa, NY – The EV industry needs electrically-conductive gaskets that combine proven environmental resistance with reliable shielding against electromagnetic interference (EMI) and radio frequency interference (RFI). Electric vehicle (EV) manufacturers and gasket fabricators have a choice of materials, but EMI/RFI elastomers from Specialty Silicone Products (SSP) are solving sealing and shielding challenges – and more.

Whether you’re designing an EV battery box, an EV charging station, or an enclosure for EV sensors or optics, you’ll like how SSP’s EMI/RFI conductive silicones have shorter lead times and are available in lower minimum order quantities (MOQs). Plus, they’re made in our ISO 9001:2015 certified facility and supplied as sheets, rolls, ready-to-mold compounds, extrusions, and molded or bonded O-rings.

Here are seven other things you need to know about SSP’s solutions for EV sealing and shielding.

EV batteries can reach operating temperatures of 45°C (113°F) and, consequently, produce a significant amount of heat. Whether their chemistry is lithium-ion, nickel-metal hydride, or lead-acid, EV batteries are enclosed in metal boxes that typically are made of aluminum. SSP’s EMI/RFI conductive silicones fill the tiny gaps between machined metal surfaces and can resist temperatures as high as 220°C (428°F).

Fires caused by EV batteries or EV charging stations can be catastrophic. To prevent thermal runaway, EV designers are using various cooling techniques and experimenting with phase change materials. Once a fire starts, however, however, what matters most is how to contain it. SSP’s EMI/RFI conductive silicones include flame-retardant silicones that conform to UL-94 V0, a widely-used flammability standard.

SSP’s electrically-conductive silicones provide thermal stability over a temperature range from -60°C to 220°C (-51°F to 428°F). These sealing and shielding materials also resist water, ozone, and sunlight, making them a good choice for EV charging stations. Silicones can resist some automotive fluids, and SSP offers EMI/RFI fluorosilicones for applications where broader chemical resistance is required.

Recently, members of Congress asked the U.S. Army to start a pilot program that examines how tactical electric vehicles would operate in the field. Previously, the Army set itself a goal of fielding hybrid electric tactical vehicles by 2025. SSP’s EMI/RFI conductive silicones are ready for duty and include materials that meet MIL-DTL-83528 requirements for elastomeric gaskets that provide sealing and shielding.

Specialty Silicone Products also serves the EV industry by making large, one-piece EMI O-rings in custom sizes that can fit any battery enclosure. At our Ballston Spa, New York (USA) manufacturing facility, we have the equipment and in-house toolroom that’s needed to expedite your project. SSP also bonds EMI O-rings in a process that reduces the risk of EMI/RFI leakage and eliminates “hard spots”.

When the volatiles in elastomers evaporate they can condense upon something else. With optics and sensor covers, yellowing can occur. That’s why SSP’s EMI/RFI conductive silicones include materials that have been independently tested to ASTM 595 outgassing parameters. Although this standard originated with NASA, SSP’s low-outgassing EMI/RFI silicones can be used on the road as well as in outer space.

EMI and RFI aren’t just problems for EV batteries and EV charging stations. These electromagnetic disturbances can also interfere with onboard systems such as backup cameras, safety sensors, GPS, and satellite radio. SSP’s conductive elastomers can help protect sensitive EV electronics, but these innovative materials are also helping to protect drivers, passengers, and pedestrians.