The second season of Formula E kicks off in October, and there's one key difference for the championship's sophomore year: custom batteries and motors. The teams are now able to experiment with the car's powertrain, which includes the e-motor, inverter, gearbox and cooling system. That means the cars will perform differently on the track, adding a little extra strategy and excitement to the proceedings. What we didn't expect, however, is the sound of the cars to change -- watch the video below for a glimpse at how they'll be screeching off the starting grid. Is it me, or do they all sound like confused felines?