The capacitance battery is a promising technology. I could see dropping one of those in my electric car after the old lithium-ion battery died. However, the cost of these batteries is quite high. You could buy lots of high price gas for the cost of one of them ($25,000). And if you do the math, and treat them as 100,000 miles of gas (their estimated lifetime), that’s over $6.00/gallon gas (equivalent for a gas car getting 25 miles/gallon using $4.00/gallon gas). I didn’t add the cost/mile for using the electricity which I heard was about $.12/mile. The electicity cost may shoot up if everyone is using these rechargable cars.
Another side effect is the production of ozone by these electric motors. Imagine an entire city firing up those electic motors in the morning.
My answer to this transportation headache is more oil drilling followed by the production of biodiesel with algae technology (or some other biochemical process).
Sure the batteries are expensive now, but I do believe that continued R&D will bring those costs down each year.
There should NOT be ANY ozone produced by the motors of modern electric cars. ALL of the ones I know of (INCLUDING the GM EV-1) used or are using an ECM DC or AC induction motor and they do NOT use brushes-—and thus —NO “commutator sparking” to produce any ozone. And as far as I know, those type of motors have only ONE moving part(the rotor) They do NOT use any mechanical switches or contacts either—all is done by PWM choppers and such that control them.