Anybody Use 2 Batteries?

[NatiDonkRyda 10+ year member]

why couldnt I just wire the 2 batteries in parallel without a isolator?

 

[jco1385 5,000+ posts]

because you will kill both batteries when you run your system with the car off. with the isolator your front battry is left alone while the rear battery supplies the system. when you are done the front battery still has a charge to start the engine so you are not stranded.

 

[NatiDonkRyda 10+ year member]

ok, thanks. and go with a 0/1 gauge wire from front to rear battery? does it matter if the batteries are different brands and voltage levels? One is a Die Hard SUV, Truck battery and the other is a Optima Red. I guess thats what the isolator is for...

 

[jco1385 5,000+ posts]

are you putting a lead acid battery in your trunk? not a good idea... and it doesnt matter if they are differnt but they must both be 12v not 16v or 18v or whatever

 

[NatiDonkRyda 10+ year member]

are you putting a lead acid battery in your trunk? not a good idea... and it doesnt matter if they are differnt but they must both be 12v not 16v or 18v or whatever

Ok, so what kind of battery should go in the trunk. I just made myself a schematic of the setup. Doesn't seem too difficult.

 

[jco1385 5,000+ posts]

if you dont want to buy any other batteries, you could just swap the red top to the trunk and put the Die Hard under the hood. post the schematic up

 

[skeptikal Premium Member]

Make sure you don't run the isolator all the time. Only when you have the car off. Your alt will charge the second battery when the car is on unless the isolator is in place.

 

[NatiDonkRyda 10+ year member]

ok ill post it...give me a minute

 

[NatiDonkRyda 10+ year member]

Make sure you don't run the isolator all the time. Only when you have the car off. Your alt will charge the second battery when the car is on unless the isolator is in place.

ok so then ill need a switch in there as well to turn the isolator on when I decide to listen to music with the car off, right?

 

[NatiDonkRyda 10+ year member]

Wiring Diagram of 2 Battery Setup: (might be hard to see)

I need a Isolator & Switch in there between the 2 batteries I guess.

 

[jco1385 5,000+ posts]

what is the "terminal"? just the battery terminal or a distro? if its a distro you dont need one. and i run 300a between the batteries, but thats just me. and yeah the isolator would go between the batteries

 

[NatiDonkRyda 10+ year member]

what is the "terminal"? just the battery terminal or a distro? if its a distro you dont need one. and i run 300a between the batteries, but thats just me. and yeah the isolator would go between the batteries

no distro here, the terminals are just battery terminal so I can run my leads to the front battery and the other lead to my amp. I'll prolly do a 250a, not sure yet. I'll ask a shop what they would suggest.

 

[NatiDonkRyda 10+ year member]

if you dont want to buy any other batteries, you could just swap the red top to the trunk and put the Die Hard under the hood. post the schematic up

Yes, that was the plan to begin with.

 

[NatiDonkRyda 10+ year member]

Make sure you don't run the isolator all the time. Only when you have the car off. Your alt will charge the second battery when the car is on unless the isolator is in place.

Yes, I will have to install switch before the isolator and mount it somewhere on my dash.

 

[mokedaddy 5,000+ posts]

Looks good. And yes the isolator goes on the power in between the two batteries. And go ahead and ground your amp to the rear battery.