Nanotechnology Products and Applications

Product Details


Product: SEPARION Ceramic Separator Membrane

Manufacturer: Evonik Industries

Product page: (external link)

Product Sector: Energy → Energy Storage → Electrical Energy → Battery



Lithium ion batteries are the most promising candidates to meet for tomorrow's mobile energy requirements. So far they had just one problem: they could not be used for large-scale power storage for safety reasons.

The weak point was the battery separator. So far semi-permeable polymer membranes have been used to separate the anode and cathode. However, these plastic separators have two major drawbacks: they are flammable and they are only stable up to 140°C. If the batteries are overcharged, the separators can overheat, melt and trigger a short circuit. And that makes them likely to explode.

Nano particles deliver excellent properties

The answer is SEPARION® - a new type of separator that gives lithium ion batteries outstanding properties. This ceramic separator from Evonik is stable to temperatures of up to approx. 700 °C.

SEPARION flexible ceramic separator
SEPARION® flexible ceramic separator.

SEPARION® is a combination of ceramics and polymers, two materials that are normally completely incompatible because of their differing temperature profiles. Now they can be combined thanks to nano-scale oxides. For example, zirconium oxide is used as a functional component in these separators to ensure the integrity of the material, its nanoporosity and flexibility.

In 2007 Evonik's SEPARION® team was nominated for the German Future Award.

SEPARION® in Li-Tec cells

Today's Li-Tec cells incorporate a ceramic separator from Evonik, making them perfectly suitable for use in electric vehicles. These world-leading flat-cell batteries combine high power density in with a compact form and outstanding safety, which naturally has top priority in high-performance batteries. These flat-cell lithium ion batteries are to be used by Mercedes-Benz Cars in the near future.