02/14/2012

• Innovative tire with extremely low rolling resistance
• High-tech design reduces conflicting goals to a large extent
• First approval from the vehicle industry – Conti.eContact exclusively on Renault Twizy

Hanover, February 14, 2012. With the Conti.eContact, Continental has a new class of tires at the starting line, tires that have been developed for the special requirements of electric vehicles (known as e-cars) and hybrid cars. In developing such tires, a particular achievement of the development engineers was in considerably lowering the rolling resistance in order to increase the travel range of e-cars and to facilitate longer operation with the electric motor in hybrid vehicles. With regard to the safety-relevant properties, Continental has maintained the usually high level of the products manufactured by the development department in Hanover. The new Conti.eContact is produced in the passenger tire plant in Korbach; an initial approval as sole tire supplier for the Twizy from Renault has been received. Continental is forecasting that there will be 2.8 million registered electric cars worldwide by 2020; representing a market share of around 3%.

Conti.eContact

Tires for e-cars must fulfill different requirements than tires for conventional vehicles. For instance, tires for electric vehicles must have substantially lower rolling resistance and a lower noise level, while the high-speed requirements are lower. In order to maintain high standards for directional stability and handling, different tread variants are produced in some cases, also for use on the front and rear axle. The tire sizes also differ depending on the type of vehicle. For example, smaller, narrower dimensions are required for light urban vehicles, while e-cars with more volume use tires for the 20-inch rims.

 The rolling resistance is 30% lower than with conventional tires. Continental engineers achieved this reduction by using a completely unusual tire dimension. With the tire size for the 195/55 R 20 test setup, the Conti.eContact has become very large and narrow in appearance. Thanks to the larger tire diameter, deformation of the tire is reduced when entering the contact patch, thus lowering rolling resistance considerably. This also means that the same load bearing capacity can be achieved as for conventional tires. In addition, the side wall of the tire was designed in such a way that less energy is lost when the tire deflects and rebounds, and the tire weight was further reduced. These measures also lower the rolling resistance. With its combination of four longitudinal grooves, high number of sipes, the absence of traverse grooves and the rigidity of the tread ribs, the tread has been optimized for low rolling resistance and low noise emission. In this way, precise handling properties and safe braking distances on wet surfaces were achieved as well. The very flat tire contour prevents the tire’s belt elements from moving more, thus further reducing rolling resistance. The side wall has also been designed for low energy consumption. Here, the developers did not use the usual edges and design elements in order to keep air resistance as low as possible. These properties make the Conti.eContact an ideal tire for e-cars and hybrids.

By greatly reducing rolling resistance, Continental aims to cut the energy required by e-cars and thus increase the operational radius of this new type of vehicle. The extended range this makes possible will significantly increase end-consumer acceptance of these vehicles, while at the same time reducing the energy used per 100 km and the time required to charge the batteries.

Continental regards the emerging trend toward electromobility as one of the key trends in the future of the automotive industry. As one of the world’s leading suppliers, the corporation wants to actively shape this by developing not just tires, but also battery systems, electrical drive systems, regenerative braking systems and numerous interior applications.

Range of sizes:

80 series:                                                        55 series:

125/80 R 13 M                                               195/55 R 20 T *

145/80 R 13 M

 *) Being planned