Awesome, if they can work out large-scale manufacturing.
The next huge problem will be current: you can charge a capacitor really fast, but having the power source capable of transferring that much electricity that fast is a problem. Not so big for little things like phones, but cars are a problem - takes me 20 hours to charge my EV on house current (1400 watts, 110v), or 4 hours on 6.6kWh & 220v, or (if so equipped ) about 30 minutes at 440v - but the latter takes a $30,000 charger and thick wiring. Replace that big battery with a giant capacitor, and the limiting factor will be wiring infrastructure, making charging as slow as is now.
BTW: I was at Kodak at the tipping point for digital. They forgot their customers were the button-pushers taking pictures, not the retailers moving pallet-loads of product. Once the public discovered endless “film” for one moderate purchase, the conversion took months - not 5 years like executives expected.
I believe this type of device will supplant the conventional battery fairly quickly, in phones, toys, portable radio/stereos, and especially digital cameras. The Big Battery companies better get on board quickly, pun intended............