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Dual Batteries

J

jdw8888

Full Member
Joined
Jul 10, 2006
Messages
47
Location
Columbus
Has anyone installed dual batteries in an '07 and up? We left the dvd players plugged in last night and found the battery dead. Jump started OK, and seems to be holding a charge OK today. I am going to have the battery tested to make sure that it is still good (it should be).

There is an opening at the drivers side at the radiator where a second battery would fit. Has anyone installed a battery there?

Thanks!
 
Sure you can add a second battery, that is what the tray is for a second battery. You will just need a isolator
 
they come stock setup for dual batteries then? I have the other battery tray is the isolater a GM part or over the counter ?
 
The 02-06 AV's have the battery up front by the radiator, and an "open spot" up by the passenger side firewall, which can be used for a 2nd battery.

The 07+ AV's are the opposite.

I don't know any that come "stock" with 2 batteries, but it definitely can be done.
 
Police Tahoe's and export GMT900's have an option for dual batteries, really simple positive cable to starter and ground cable to firewall.

Parallel setup

25825642 Cable
15888242 Cable
14005061-RETAINER;AUX BAT HOLDOWN
11509853-BOLT;AUX BAT HOLDOWN

Isolated setup
15942731-CABLE;NEGATIVE AUX BAT
15942730-CABLE;POSITIVE AUX BAT
25862351-CABLE;POSITIVE AUX BAT RH
21021808-NUT (QTY 2)
11517293-NUT (QTY 2)
12135194-RELAY;AUX BAT
15881616-COVER;AUX BAT POS JUNCTION BLOCK
14005061-RETAINER;AUX BAT HOLDOWN
11509853-BOLT;AUX BAT HOLDOWN
 
Troublemaker said:
The 02-06 AV's have the battery up front by the radiator, and an "open spot" up by the passenger side firewall, which can be used for a 2nd battery.

The 07+ AV's are the opposite.

I don't know any that come "stock" with 2 batteries, but it definitely can be done.
Click to expand...

That open spot I saved it for my train horn  >:D
My second battery is inside my AV, underneath the back seat, fits perfectly, and it is closer to my amp. You just gotta make sure you buy a sealed battery, other way if you roll a truck, you may have some acid in your truck.
I love Optima batteries.
 
You have a battery inside the cab OMG
 
TXSZ66AVLANCHE said:
Police Tahoe's and export GMT900's have an option for dual batteries, really simple positive cable to starter and ground cable to firewall.

Parallel setup

25825642 Cable
15888242 Cable
14005061-RETAINER;AUX BAT HOLDOWN
11509853-BOLT;AUX BAT HOLDOWN

Isolated setup
15942731-CABLE;NEGATIVE AUX BAT
15942730-CABLE;POSITIVE AUX BAT
25862351-CABLE;POSITIVE AUX BAT RH
21021808-NUT (QTY 2)
11517293-NUT (QTY 2)
12135194-RELAY;AUX BAT
15881616-COVER;AUX BAT POS JUNCTION BLOCK
14005061-RETAINER;AUX BAT HOLDOWN
11509853-BOLT;AUX BAT HOLDOWN
Click to expand...
I take it these are all GM part numbers?
 
MS03 2500 said:
You have a battery inside the cab OMG
Click to expand...
gm's has been dong this for a while,ex: 00'-05' buick lesabre has the battery under the rear seat. (n) could be worse 03'-08' porche cayenne has the battery under the driver seat :eek: :eek:
 
Thanks for the warning jimbo. I had a volkswagen beetle that had one under the back seat.
 
MS03 2500 said:
You have a battery inside the cab OMG
Click to expand...

I'd only do this with an Optima cause they are completely sealed. You can turn them up side down, won't leak.

Also I didn't know that someone else had batteries inside the vehicle. I thought I was the only silly one.
Thanks for the info. It's a relief.

Also keep in mind that if you have to charge it, keep your doors open a crack or you'll blow out the windows.
 
Most times that I have seen that done it was in a compartment that was vented to the outside. Batteries will get warm.
 
MS03 2500 said:
Most times that I have seen that done it was in a compartment that was vented to the outside. Batteries will get warm.
Click to expand...

I would say that a battery gets pretty warm in an engine compartment (@ 209 degrees) as compared to an air conditioned cabin...and in the winter keeping the battery inside is easier on it, because the cold, as we all know, kills batteries.  So if it's a sealed dry cell,,,have at it.
 
Chrome AV said:
I'd only do this with an Optima cause they are completely sealed. You can turn them up side down, won't leak.
Click to expand...


Wrong, they are not completely sealed- those gray disk type things you see on the top of the battery, those are vents.  When bulk charging they do off-gas, which is vented out of those gray disks.  Mount your optima upside down, discharge it, then toss a charger on it, watch it leak...
 
I did the install on a 2011, only because I had a 2 month old yellow top...  I went the parallel option.

IMG_6697.jpg


IMG_6690.jpg


IMG_6691.jpg


IMG_6689.jpg


 
I had a 2 batt setup in my '05 silverado, but it was mainly for car audio. Both under the hood 1 at the rad & one in the pass side. I did also choose to go parallel with them (no isolator). I also had a HO alt (275amp) to help keep them charged. I plan on adding the 2nd batt to the Avy as well as the HO alt, but no major system in this one. It's to nice for me start destroying it, lol. Simple system with this one.
 
I used the isolator because I use it for toys and don't want to run down the main battery when the engine off.
 
make sure you buy a sealed battery, other way if you roll a truck, you may have some acid in your truck.
I love Optima batteries
if you roll your av id think the battery acid would be the least of your problems  ??? just saying
 
48548 said:
I did the install on a 2011, only because I had a 2 month old yellow top...  I went the parallel option.

IMG_6697.jpg


IMG_6690.jpg


IMG_6691.jpg


IMG_6689.jpg
Click to expand...

Whered ya get the parts to do it? I really want to do this so I will have the power for more lights. Do I need a bigger alternator though?
 
Although there are vehicles that have mounted their batteries inside, it is not a good idea regardless of type.  Issues can arise where they gas off even when not being charged. This can be lethal in an enclosed space.

In a collision or even an accidental mishap, if the positive and negative leads cross, it can cause the battery to explode. Again, this could end badly if it is in the interior of your vehicle.
 
Touching on an old thread....

ALL automotive batteries off gas and have a vent to let this out... It releases hydrogen gas which is highly explosive.
Yes even Optima batteries...

All modern internally mounted batteries are designed with a venting system to prevent the interior of the vehicle from exploding. If you have a battery mounted inside your vehicle and it is not in a vented battery box that is vented to the exterior of your vehicle you are asking for problems. It is also important to insure there is no sparking around a battery as well because it will explode when charging.

Don't assume a battery can not leak regardless of what the manufacturer states. I have had multiple optima batteries leak acid in the past. It may have been a bad batch and not a normal issue but it was an issue for me so be aware...

Rodney
 
I know this may be way old... but I was looking at doing this... I was wondering if anyone has any pics of the parallel setup. I am going red to red (+) and black to black (-) from secondary battery to the primary?

if i was to use the isolated setup... would I have to have everything i wanted to run off of it hooked up to the secondary battery? I looked at the isolator part, and saw it had the two nuts, and it looked like an input for a wiring harness... is it something thats just there dangling in every truck, or is there more to it?
 
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