The very latest EVs, including the upcoming Audi E-Tron, use large lithium ion battery packs
Carbon nano-tubes could offer drastic reductions in weight to enhance efficiency
A fast-acting carbon ‘ultra-capacitor’ that could take 30% off the weight of a lithium ion EV battery pack is under development in France.
The ultra-capacitor, which is built using carbon and graphene nano-technology, is claimed to store and discharge electrical energy much more quickly than a lithium ion cell.
“Our advantage is the speed of charge and discharge,” said Ulrik Grape, chief executive of NAWA Technology, the company responsible for the device. “Our carbon battery can pick up energy from regenerative braking and supply it back to the motor very quickly.”
Ultra-capacitors offer very fast energy transfer but don’t have a large storage capacity. According to NAWA, the ultra-capacitor could be integrated into a lithium ion battery to provide instant power for improved performance, while reducing the number of charge and discharge cycles the main battery performs, thus extending its life.