The car batteries of the future will have to be small, light, and considerably more powerful. Degussa AG of Dusseldorf is developing novel materials for lithium-ion batteries that make possible a new generation of starter batteries weighing only 2.5 kg. The new batteries are now being used - under the demanding conditions of motorsport - in racing car from the British manufacturer Lotus.

"This is an extremely light and highly efficient battery," says Klaus Hedrich, head of Degussa's Automotive Industry Team. One of the most important aims in motorsport is to keep the racing cars as light as possible. In comparison with conventional starter batteries, which weigh between 15 and more than 20 kg, this design results in unprecedented low weight.

A wealth of Degussa expertise has gone into the interior of the battery. At the heart of the battery is SEPARION^?, a separator produced by the world's largest specialty chemicals group, which consists of an ultra-thin ceramic composite material. Highly efficient and safe electrodes and electrolyte additives from Degussa are also used. These materials make lithium-ion cells significantly more powerful and, most importantly, much safer. The cells have, for example, passed without any problem the extremely exacting overcharge and nail penetration tests, in which a nail is driven through the battery. When conventional separator materials were used, on the other hand, there was smoke development and in some cases even outbreaks of fire.

"This lithium-ion technology will be used in the future also for energy storage in hybrid vehicles," says Sven Augustin, who is responsible for Automotive Marketing at Degussa. Hybrid vehicles are based on the concept of storing the braking energy in the form of electrical energy and utilizing this if required via an additional electric motor drive in the vehicle. This makes for more enjoyable driving without running up exorbitant gas bills.

The battery has been tested in motorsport, with excellent results. "We've been astounded and delighted by the low weight and the size. You can clearly feel the power of this technology," says Martin Roos, whose racing team RED Motorsport is using the battery in a Lotus. If the engine in another racing car packs up, this usually means premature withdrawal from the race. But the Lotus in its racing version can be started again safely, even in difficult situations.

"We're using our involvement in motorsport to test further components from Degussa's development departments under the toughest conditions," says Klaus Hedrich. The Lotus, for example, has a specialty coating that uses matting agents from Degussa in its production. The windshields for these racing cars are also of a special lightweight construction, using a specially developed scratch-resistant acrylic from Degussa. This reduces the weight of the windshield in the Lotus used for the Dutch Supercar Challenge from 9.5 to 4 kg.

In China, Degussa expanded the Lithium ion battery material activities with the Joint Venture Degussa ENAX for high performance elctrode production in Shandong Province two years ago. In the next few years the company intends to invest about 100 million euros annually in China and Lithium ion batteries market is with no doubt one of their main focus areas.

(China.org.cn February 28, 2007)