Rechargeable Battery?

depends on what kind of bulb you are going to drive with it, if you are dealing with a medium power bulb, like say, a 35W-50W application, I would lean towards recommending sanyo eneloop cells for their simplicity of use and low self-discharge. (they require little to no break in or maintenance cycles). If you are planning on a 50-100+W mod, go with a cell designed specifically for high current, like an elite 1700.

as for a charger.. if you are looking for cheap something like this will do:
http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=836

but a more sophisticated hobby grade pack charger (usually ~$100-200) is recommended.
 
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