This graph shows the power and energy density of graphene-coated porous silicon supercapacitors compared with that of capacitors made from porous silicon alone and of activated carbon. (Source: Vanderbilt University.)
We've all read about the hours required to charge electric vehicles (EV). For example a Chevy Volt takes 8 hours at 120 volts or 4 hours at 240 volts. The inductive charging of the Volvo sounds really impressive in only 3 hours. HOWEVER the Volvo is doing much less charging. While the Chevy Volt is charging at 1,440 watts, the Volvo is charging at 300 watts. The inductive approach (not surprisingly) is moving much less power into the battery. The statistics only sound so good because it is a smaller battery.
If my numbers are right, it would take nearly 5 times longer to charge wirelessly - I'm happy to manage a plug connector with that kind of time savings. The exceptions would be for a highway with embedded charging circuits that charged my car as I drove (plugs and wires won't work) or a parking lot that would charge my car without having to find a cord and charging station.
Getting this to work in silicon is interesting...any time you can do something in silicon it eventually wins as the material and its processing is very well understood and perfected...see silcon solar cells, despite the fact that other solar cell technologies are available silicon is a king here capturing 90+% of the market...the same with silicon chips of course, despite GaAs and InP threats it commands 90+% market share...will silicon super cap be the next silicon specialty? Kris