JD wrote:
Yea.. I'm not real sure about the units here... but they do site a
power density of 2700W/Kg see:
http://www.a123systems.com/html/tech/power.html

They're pretty clearly talking about power density, not
energy density. Both their language and their units
reflect power density.

Power density isn't the issue for long-distance cruising.
It might be somewhat relevant if you were wanting to
build the fastest possible dragster for a 100 yard sprint.
But energy density is the problem that most battery
powered vehicles have when compared to petroleum
powered vehicles, especially for long distance cruising.