How to wire and use 2 Car battiries?

Question

I will be installing 2 battires in my car one under the hood the secound one in the trunk is it ok to run a the postive to the on in the hood to the postive to the trunk and then hook the neagtive to the ground in the trunk??

To simplify postive from Hood to postive trunk

neagtive trunk to ground/chassis

Answer 1

You must have a battery isolator to run two batteries. If you just connect them in parallel they will not charge evenly. Go to auto supply and look at isolators, they come with instructions.

Answer 2

they have to be ran in parallel to work properly ,positive to positive, neg. to neg. , you have to run both cables from one to the other.