New Rogers Corp. materials control thermal runaway in electric vehicles
By Geoff Giordano
With e-mobility gaining traction, chemistries to prevent thermal runaway—i.e., temperature spikes in failing electric vehicle (EV) batteries that can grow into raging fires—is a key focus of Rogers Corp.
This is vital as EVs are poised to become what cell phones were to consumers about 10 years ago, predicted Polina Ware, global director of research and development for elastomeric materials solutions, in her ANTEC® presentation. An EV is “going to be, in a way, a personal computer on wheels that may become an extension of who we are, our personality.” She noted that by 2026, 50 percent of passenger vehicles are expected to be fully electric or hybrids.
In the past six months, Rogers Corp. has designed next-generation elastomeric chemistries and composites for EV pouch cell battery packs that are intended to prevent thermal runaway at the single-cell level while remaining compressible, Ware said. Elastomeric pads sit adjacent to failure points in a battery, protecting pouch cells as the battery expands and contracts during its functional life. Those pads are the first line of defense for delaying thermal runaway and must remain flexible to withstand dimensional changes.
Rogers uses two approaches: a composite method employing urethane or silicone foam with a thin insulation layer of ceramic or glass fibers, or multifunctional additives within the foam. By considering stress/strain distribution and force at distribution curves, Ware explained, these innovative elastomeric materials are simultaneously compressible and protective.
So new are these technologies, she added, that tests for thermal runaway prevention are still being developed. A hot plate test Rogers developed with automotive industry customers found that the company’s new materials performed somewhere between a foam alone and a non-elastomeric aerogel. Then, using the industry-standard NREL (National Renewable Energy Laboratory) test to assess thermal runaway in a three-cell pouch, a nail was driven through a battery cell. “For some of our materials, we completely shut down the thermal runway.”
The goal is to develop fully sustainable urethanes and silicones for battery pads within a companywide sustainability roadmap for designing toxic chemicals out of its products, Ware said.
View on demand: Ware’s presentation, “Emerging Technologies That Are Changing the Future,” will be available on demand to ANTEC® attendees and those who register for access after the conference.