Season 2 of Formula E, which begins again in October, will get underway under a smog of new technical regulations. The FIA has relaxed its rules which now allows teams to develop their own batteries and motors.
The powertrain, invertor, e-motor, gearbox and cooling systems can also now be fine tuned for and the changes made by each competing team has altered the sound of these battery powered racers.
To us they sound like radio controlled drones, but a lot better than the V6 Hybrids in Formula One.
