[quote=Terminal]
Mr. Helper models have a special fusion generator courtesy of General Atomics International.
[/quote]

Ok, thanks. That means no recharging. You might want to collect them if you kill any though. Spare 200kw generators might come in handy.
[url=http://fallout.wikia.com/wiki/Mister_Handy] Mr. Handy Wiki[/url]
Also, the type IIs had rechargable energy cells, so I'll say that's where the Enclave got the schematics for them.