Extension cord?
If I was an artifically intelligent computer, and I needed to power my robot army, and I didn't need to worry about the saftey or well being of those pesky humans, then I'd just go with an unshielded nuclear power source. Like interstellar spacecraft, you just stick a bit of plutonium in a little metal container and use the radiation from it to heat water and generate power via steam.
Voila, a battery with a half life of a thousand years. :-)
If I was an artifically intelligent computer, and I needed to power my robot army, and I didn't need to worry about the saftey or well being of those pesky humans, then I'd just go with an unshielded nuclear power source. Like interstellar spacecraft, you just stick a bit of plutonium in a little metal container and use the radiation from it to heat water and generate power via steam.
Voila, a battery with a half life of a thousand years. :-)