Evonik Industries, BASF, Bosch, Volkswagen, and Li-Tec, Evonik’s mid-sized partner in the manufacture of large-scale lithium-ion batteries, are embarking on an R&D initiative with the Federal Ministry for Education and Research (BMBF) for the development of “lithium-ion batteries for mobilizing regenerative energies of the future and increasing efficiency in the conversion of fossil and regenerative energies.”
The BMBF is backing the three-year initiative with €60 million (US$87 million) in funding.
With the BMBF as a strong partner, the topic of lithium-ion batteries is gaining enormous importance again in Germany. The initiative, which will be an equal incentive for research and industry, is covering all stages of the value-added chain of this future-oriented product for the first time.—Dr. Alfred Oberholz, member of the Evonik Management Board with responsibility for R&D development in the Chemicals Business Area
As of 12 September 2007, what was Degussa became the Chemicals Business Area of the new Evonik Industries. Degussa had developed the SEPARION flexible ceramic separator membranes that replace plastic membranes for separating anode and cathode in lithium-ion batteries.
SEPARION consists of a flexible substrate, normally a non-woven polymer, coated with a porous ceramic layer. The pore size can be selectively set by an appropriate choice of ceramic coating material.
According to Evonik, the ceramic properties of the separator make it more temperature-stable than conventional polymer separators used in lithium-ion polymer batteries, and therefore contribute towards preventing short circuits in the battery.
If a first-generation large-volume lithium-ion battery is overcharged, the heat build up can melt a polyolefin based separator leading to thermal runaway generating temperatures in excess of 800° Celsius. The ceramic SEPARION separator, however, delivers inherent thermal and chemical stability to the system, according to the company. (Earlier post.)
The team responsible for the development of the SEPARION separator has been nominated for the German Future Prize, to be awarded by German President Dr. Horst Köhler on 6 December 2007.
Not a cell producer, Evonik produces components, including lithium-ion electrodes under the trademark name LITARION. Degussa also had begun additional electrode production for large-volume lithium-ion batteries at the Li-Tech GmbH (SK Group) site in Kamenz/Dresden.
LITARION cathodes are based on a Li-Mn-Ni-Co (NMC) chemistry offering enhanced safety and long-term stability. In addition, a cathode solution based on Mn spinel chemistry (LMO) is also offered. The anodes use graphite or hard carbon material.
In the next phase of the partnership, and at the same site, L-Tec will use these electrodes to produce lithium-ion cells, which will later be processed to batteries.