Improved properties for lithium-ion batteries

Thanks to nanotechnology, Evonik has developed a novel technology, a flexible ceramic separator membrane marketed as SEPARION®. This is a key component in large-scale, high-performance batteries based on Li-Tec's CERIO® technology. It ensures a high performance and long service life combined with increased safety.

SEPARION® flexible ceramic separator

Nanotechnology is the key

The nanomaterials on the surface of SEPARION® allow sintering of the ceramic at low temperature so it can be combined with a polymer nonwoven. The sintering process, which comprises the solidification and bonding of particles to form this ceramic material, can take place at a sufficiently low temperature to allow the two layers to be combined. The ceramic structure of the membrane means that it is heat-resistant up to 700 °C, thus reducing the risk of fire.

The membrane is used as a separator between the electric components in the battery: it separates the positive and negative poles of the battery cell to prevent short-circuits. In addition to the separator, an anode and a cathode are required to create a current in a lithium-ion battery. SEPARION® technology plays a key role in driving forward the development of electric and hybrid vehicles for everyday use, thus reducing fuel consumption and environmental impact.

Li-Tec Battery GmbH, a joint venture of Evonik and Daimler, plays a key role in the battery technology alliance formed by these two companies. It produces high-performance CERIO® battery cells incorporating SEPARION® ceramic membranes. These cells are marketed to industrial customers for mobile and stationary applications. In a first serial production project for electric vehicles, Deutsche Accumotive GmbH, another joint venture of Evonik and Daimler, will use Li-Tec CERIO® cells to produce batteries for vehicles. As a system supplier, Evonik also supplies anodes and cathodes for these battery cells.