This is one of the better articles I've read about EEStor. It covers all the traditional angles while underscoring that EEStor's technology isn't just about electric cars but involves practically thousands of uses in thousands of types of devices. Here's an excerpt:
An electric vehicle needs a source of electricity that’s as light and powerful as possible. A lithium-ion battery, the emerging state-of-the-art battery for electrics and hybrids, has a “specific energy” (electricity per unit of mass) of 120 watt-hours per kilogram. EEStor says its light ceramic ultracapacitors have a specific energy more than twice that: 280 watt-hours per kg. By contrast, a lead-acid gel battery used in golf carts is rated at 32 watt-hours.
The article goes on to point out that BMW is evaluating ultracapactitors