so does anyone know how the whole....thingy works where you ggive the subs their own battery....?
do you jsut place it in the trunk and run the battery wire to it?? cause i have no idea, but im thinking about doing it.....

help? casue i cleary dont know much on how this works

Subwoofer (or any speaker) doesn't need a separated power source.
The thing that really draws power is the amplifier.
If your system is drawing lot of current, you might need a capacitor or a higher capacity alternator and battery.
What is your current sound system power spec/rating?

to add an extra battery, just run a power wire from the front to the back, and ground it! I have one in the back of my celi for my amp too!

do you need to run anything from the alternator to charge the battery?