4x4junkie
Explorer
how long would a strip run off of some double A batteries?
If you dimmed it way down it probably could last several hours to maybe a couple nights... Though at that point it probably wouldn't be much brighter than many of the other battery-powered options that are available (my tests show a full 5-meter LED strip (undimmed) pulls roughly 2¼ amps (between 25-30 watts) when hooked straight up to a 12 volt source, with a total light output I estimate between 1600-1800 lumens).
I think you're best off just hooking that to a cig-lighter plug with the dimmer wired inline and calling it good.