If you are after a simpler alternative these may help, they are in
Australia, but I'm sure they will be available somewhere in the states:

http://jacek.customer.netspace.net.au/charger.html

and

http://www1.jaycar.com.au/productVie...Max=&SUBCATID=

Hope this helps,
Fraser

"DaveH" wrote in message
...
what the hell? you already have the inverter. something else could be
more
efficient, but not THAT much more.

"Dennis Pogson" wrote in message
...

"Josh Assing" wrote in message
...
My laptop uses 18 volts... Right now; i use an inverter to go to 110,
then use
hte laptops power supply to return to 18.

Seems like if I could just go 12vdc to 18vdc it'd be more effecient.

Thoughts?

And if so; any clues on where I can find info on building something
like
this?

Don't bother, just stay as you are with the inverter, it really isn't
worth
it. To get the amps you need to run a laptop, the circuitry is more
costly
than what you are doing now. This post will result in howls of protest
from
the electronics whizzkids, but I'm telling you, it's a jungle out there!