Freudenberg Sealing Technologies’ new thermoplastic for EVs resists melting even at 1,200deg C

Freudenberg Sealing Technologies has announced development of a new thermoplastic that can handle extreme heat of up to 1,200 deg Celsius without melting. This development could play a significant role in improving fire protection in electric vehicle drives.

The material is called ‘Quantix ULTRA’ and it resists melting even at extreme temperatures of up to 1,200 degrees Celsius. Processing the material in injection moulding is both versatile and economical. Given that today’s vehicles call for lightweight construction, its lower density compared to metallic materials is an additional advantage, states the company. The first series application is now underway, as a flame protection barrier for cooling system parts in an electric car’s lithium-ion battery.

Electric cars with lithium-ion batteries have a range that is suitable for everyday use and require a high degree of safety. Various safety measures are being implemented to make sure that any thermal runaway of the battery is prevented or delayed.

According to Freudenberg Sealing Technologies, Quantix ULTRA can withstand very high temperatures. It does not melt or ignite. In laboratory tests, a two-millimetre-thick material sample can even resist an applied flame with a temperature of 1,200 degrees Celsius for over 25 minutes.

Further tests simulate the emission of hot particles under high pressure, which can occur if the gases in battery cells are abruptly discharged. Quantix ULTRA withstands the stress test for 20 seconds. A two-millimeter-thick aluminum sample only takes two or three seconds to be destroyed.

“The new material doesn’t melt at high temperatures; instead, it exhibits elastic behavior that can be compared to elastomers,” explains Kira Truxius, Material Expert Thermoplastics at Freudenberg Sealing Technologies. “It also has a glass transition temperature that is 53 Kelvin higher, which means that it retains its rigidity and flame protection over a significantly longer period of time. When you add up its qualities, Quantix ULTRA is at the very top of all currently known plastics.”

Freudenberg Sealing Technologies is using this innovative material to produce flame protection barriers for the cooling system of lithium-ion batteries, for example. As of February 2024, these will be used for the first time by a car manufacturer in series production vehicles.

Suitable for multiple applications

Quantix ULTRA is suitable for all applications with high requirements for fire protection and lightweight construction. Moreover, it is not limited to specific geometric shapes. The material can be processed into films, for example, to be implemented in battery-electric drives. Other areas of use include enclosures for power supply units, media-carrying lines, cable insulation, battery housing covers and components for electric motors.

Patented know-how for focused material properties

The base material of Quantix ULTRA is a thermoplastic that is already temperature resistant. The precise addition of fillers such as glass or carbon fibres reinforces the mechanical stability even under enormous heat. The additional cross-linking of the plastic molecular chains ensures that the component maintains its shape even under extreme conditions. The material properties can be adjusted with a focus on the specific application.

“Our patented know-how consists of the precise addition of suitable materials that create bridges between the molecular chains. The patents are the result of successful teamwork,” explains Dr. Björn Hellbach, Material Expert Thermoplastics at Freudenberg Sealing Technologies.

Picture: Freudenberg Sealing Technologies