I think thats the ultimate solution
but also I think that once our entire society switches to storing energy in carbon based graphene, we will realize theres some crazy fuckery with carbon and our planet and we will enter an ice-age due to absorbing so much carbon from the environment (the opposite of global warming, putting too much carbon into the environment)
But Batteries themselves are negliable in the long run. Think of this:
your battery pack LiIon is rated for 500-800 cycles of 0-100% then back to 0 again.
1 cycle equals 100-0-100
500 cycles and your pack is only 75% of capacity (this is much worse than real world)
1 cycle = 100 miles of range (common EV car, Nissan Leaf)
500 x 100 = 50,000 miles of driving before you will begin to have an issue with your propulsion system.
this is a worse case scenario, where you only get 50,000 miles of troublefree operation out of your drivetrain. Most Powertrain warranties are 40,000 miles. Your battery in a Prius or a LEAF is guaranteed for 10 years.
By all metrics, an EV battery system is more reliable and just as efficient if not more than your gas system.