Close, I'd say that the problem is with electric delivery, not storage. Though storage has issues, too.
Unless someone comes up with some sort of a battery swap-out....pull into a "Swap station", yank the old battery out of the car, and put in a new charged one ...
Otherwise, the conductors required to deliver a full charge of electricity to the battery in a "reasonable" (say <10 min) will be as thick as your thigh, and about as flexible. To say nothing of the variable load it would throw on the existing (overtaxed, underpowered) infrastructure.
Heck, places like California already deal with rolling blackouts due to lack of generation infrastructure. What happens when 20 million cars' worth of daily demand gets dumped on the grid? And increased demand drives up cost, which lowers ROI, and so on and so on.
Pure electric, isn't the answer. Not now, and for the forseeable (20-ish years?) future.
Excellent points all around. Both Storage AND Delivery problems go hand in hand, as improvement in either lessens the impact on the other.
For example, let’s say with current lead-acid batteries, I have some car that has a meager 75 mile range (meager by gasoline standards). If improvements in DELIVERY let me somehow charge the batteries in 10 minutes, I am less concerned. I could drive 1 and 1/2 hours at nominal freeway speeds, stop for charge, a stretch and a chance to take a leak.
Conversely, if I have “super” batteries that let me go 400 miles on a charge, but they take 8 hours to refill, I am less concerned, as for most of my use, 400 miles in a day is fine, and I can let the thing charge overnight.
Electric infrastructure to support this is a whole ‘nuther ball of wax...