During the EVS 25 electric vehicle expo in Shanghai earlier this months, Honda engineers presented a glimpse into the development of an advanced high-performance electric motor that Honda had designed as part of a KERS (Kinetic Energy Recovery System) intended for its 2009 Formula One race car.
The stunning design shows how much money was invested by Honda before it withdrew from Formula One. Although alternatives with a flywheel were tried out, their main focus was on a battery system, albeit with the batteries housed in nosecone.
The team judged that this position could retain the packaging and optimization of the sidepods, while batteries low in the front helped frontal weight bias. The design went as far as housing a water cooler inside the nose to cool down the battery pack.
Power from the batteries was transferred through an oil cooled motor in the left hand sidepod.
Vehicle testing commenced in April 2008 with straight course accelerations, and progressed into circuit tests at Silverstone the following month. Additional circuit tests were conducted at full load in September and showed that it could improve laptimes from 2 to 3 tenths, depending on the circuit.
The final design achieved 7.8 kW (10.46 hp) of power per kilogram, close to Honda's design goal of 8 kilowatts per kilogram. Peak motor efficiency was 99% and peak generator efficiency during regen was 93%. Motor weight was 6.9 kilograms.
Read more about the battery system and details of the flywheel system at:
http://www.greencarcongress.com/2010/11 ... -7-kg.html