Batteries and Energy Storage

Many friends and colleagues are deeply devoted to Lithium battery technologies. There is some great research at my alma mater Dalhousie University.
http://fizz.phys.dal.ca/~dahn/jeffDahn.html

But, though not very exciting, the past, present and potential of Ni-x chemistries and ultracapacitors seem very real
http://en.wikipedia.org/wiki/NiMH_battery
http://en.wikipedia.org/wiki/Nickel%E2%80%93hydrogen_battery
http://en.wikipedia.org/wiki/Nickel%E2%80%93iron_battery
http://en.wikipedia.org/wiki/Nickel%E2%80%93zinc_battery
http://en.wikipedia.org/wiki/NiCad

http://en.wikipedia.org/wiki/Electric_double-layer_capacitor

One must make the mental leap to supporting such with electronics and devices (charge and discharge) tuned to a charge bucket instead of a chemical cell.

And when it comes to equations involving battery mass and volume (transportable), it is hard to beat Lithium systems.