connecting an extra battery to the main battery

[jnguyenn16]

hey guys I was wondering if there was a way to connect the two batteries to where I can charge the battery when the car runs. I'm running a 1500 watt polk amp with 4 Kenwood speakers and a Sony head unit which came with my teg. the set up I have right now is draining my battery fast so I was thinking about an extra battery in the trunk connected to the main battery so I can run my 2400 watt rockford fosgate amp and a 15" treo ssx competition sub.

sorry for the long post but I'm a noob and I just got confused by the research I did

 

[BeatBox]

you run a power wire to the back, but fuse the wire 12inches or so from each battery(total of two fuses)
wire will go pos to pos
then the negative on the rear battery make sure to ground it off to the car
run your amp off the second battery

OPTIONAL: if u can, run a negative from the front battery all the way back

in my car i have 4 runs of positive going front to back, then 2 runs of negative front to back

 

[jnguyenn16]

you run a power wire to the back, but fuse the wire 12inches or so from each battery(total of two fuses)
wire will go pos to pos
then the negative on the rear battery make sure to ground it off to the car
run your amp off the second battery

OPTIONAL: if u can, run a negative from the front battery all the way back

in my car i have 4 runs of positive going front to back, then 2 runs of negative front to back

thanks man but just to make sure I'm either going to put the negative to negative or ground my second negative. right?

if I were to run neg to neg what are the benefits

 

[BeatBox]

yup negative to negative, or ground that second battery off the vehicle

it just makes everything ground up the best you can, if you ground it just in the back its good but going to ground to ground is better

on mine i have it both ways, front to back negative and ALSO grounded it out back
this is where i grounded out the back batteries(i have two)

before running all my wires

also make sure not to forget to run two fuses on the power wire so it stops anything from burning up incase either battery has a problem
upfront

out back (ran my fuses on the side of the battery piece)

 

[jnguyenn16]

thanks a lot man +1