In March 2012 Williams Hybrid Power, a sub division of Williams Advanced Engineering until its sale to GKN in April 2014, announced an association with Audi Sport to become the hybrid system energy storage supplier for the Audi R18 e-tron quattro that competes in the FIA World Endurance Championship.
For the Audi R18 e-tron quattro Hybrid Power designed an entirely new, ultra-lightweight electric flywheel and associated power electronics and the company worked closely with Audi engineers to fully integrate its unique electric flywheel into the car. The system will provide 150kW of power and have a top rotor speed of 45,000 rpm.
The defining features of Hybrid Power's flywheel made it the prime energy storage candidate for Audi’s project when compared to other technologies such as batteries, ultra-capacitors or mechanical flywheels. The main benefits of the system are a high power density and correspondingly low mass, high efficiency energy transfer to and from the e-storage, the ability to continuously deep power cycle and an insusceptibility to performance or life degradation over a wide range of operating temperatures. In short, the technology is perfectly suited to the high performance demands of endurance racing.
The Audi R18 e-tron quattro made history in June 2012 by becoming the first hybrid car to win the 24 Hours of Le Mans, with its flywheel enduring the toughest automotive test known to man. This success was matched at the 2013 24 Hours of Le Mans, with the flywheel powered Audi R18 e-tron quattro once again taking the chequered flag.