WEINHEIM, Germany—Freudenberg Sealing Technologies is making strides toward sustainability in the world of electric batteries with the development of a new PFAS-alternative sealing material for electric batteries.
The new injection molded material "delivers superior sealing performance, ensures battery life and meets increasingly stringent environmental regulations" with elastomer materials in anticipation of an eventual European PFAS ban, the firm said April 10.
Freudenberg said that O-rings made from the new material prevents electrolytes from escaping the battery cell, and keeps impurities away from the cell's interior.
"Premature capacity loss, which has been observed in cells sealed with conventional elastomers, can result from minimal but still present impurities in the sealing material," Stefan Schneider, head of material development at the O-Rings lead center, said in a statement. "The infiltration of moisture into the cell has a similar effect, as it can cause the decomposition of electrolyte components. These aspects were considered when the new material was developed."
In lieu of a thermoplastic, the new material is a high-performance elastomer according to David Kuhne, application engineer at Freudenberg Sealing Technologies. Although thermoplastics have become the norm for battery seals and e-mobility applications, Freudenberg said that its new material is able to outperform many common thermoplastics thanks to strong, cross-linked molecular chains that are able to stand up to elastic deformation.
"You shouldn't think of a battery cell as a rigid construct—it 'breathes,' " Kuhne said in a statement. "When the temperature in the battery cell rises from ambient levels to—as a rule—ranges of up to 60°C (140°F), the cell expands and then contracts in the same way as it cools. Elastomers show significant advantages over thermoplastics during this continuous stress."
Development of the new material was focused on both economic and sustainability aspects, according to Freudenberg officials. The firm added that the new material series also complies with national and international environmental standards in both the U.S. and Europe.
But to stay on the International Energy Agency's schedule to net-zero emissions, the worldwide EV fleet must expand more than 450 percent before 2030, from 45 million to 250 million worldwide.
The company expects a "sharp increase" in battery demand before the end of the decade in order to stay on track with this schedule. Kuhne noted that Freudenberg feels prepared to up production in the near future, and that the company's new product will be both highly effective and highly sustainable when that time comes.
"As a development partner for customer-specific projects, we contribute many years of expertise in materials and innovation," Kuhne said. "Thanks to our advanced analytical methods and vertically integrated manufacturing processes, we can develop and implement competitive production solutions with great agility."
