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Topic Review (Newest First)
05-09-2013 10:05 PM
AC0QR The wiring diagram indicates that connecting them in parallel is exactly what he is doing...
05-09-2013 08:45 PM
Originally Posted by Jerry Bransford View Post
The only way batteries can be connected in parallel without one damaging the other is if both batteries are identical in every way including age.
This is simply not true, we connect truck batteries (the average class 8 truck takes 4 very large high CCA batteries) 1,2 and 3 or 4 at a time all the time, no ill effects. Some large equipment that takes 8 or 10 or more rarely get all changed at once, you use a temp gun or voltmeter to find the weak batteries in a set.
05-09-2013 08:32 PM
Jerry Bransford
Originally Posted by Texas2070 View Post
Is optima a good battery? Mines great and has never let me down. I was just wondering.
Optimas used to have a superb reputation but not since Johnson Controls bought them & moved all of their manufacturing down into Mexico. I had two Yellow Tops & one Blue Top all fail prematurely, I wouldn't run an Optima any more if it were given to me.

Nice job on the review Reketr. I noticed the mix of Red Top & Yellow Top, just remember to never let them get connected in parallel with each other. The only way batteries can be connected in parallel without one damaging the other is if both batteries are identical in every way including age.
05-09-2013 08:27 PM
DJs97TJs Any pictures of the control you use to switch between the batteries?
09-08-2012 06:09 AM
little1989jeep My red top has survived a jeep fire, wrecked truck, & now it lives in our Massey 235 with no alternator
09-08-2012 04:00 AM
Texas2070 Is optima a good battery? Mines great and has never let me down. I was just wondering.
11-21-2011 09:53 PM
Itsfun00 Thats sweet... I need to do that and was thinking of using the other tray instead of squeezing it in. But now I know they will fit. Thank you!!
11-21-2011 08:25 PM
Jeeprogue Nice Set-up btw, the other tray is not for if the steering wheel is on the other side (my TJ is a Righty) it is actually for the ABS module.
10-16-2011 11:09 PM
2005TJSOCAL I like the set up, thanks I was looking at the other side tray, probably for when the steering wheel is on the other side? I think I m going to put my tank and compressor on that side. Do you have air too? Thanks for pics
04-12-2010 01:25 PM
Master Switch?

Nice setup! What do you think is the feasibility of using a heavy duty power-switch as an axillary battery master switch instead of an isolator?
09-13-2007 02:59 AM
dwdrums801 yeah i need another battery my lights dim just with my stereo loud and when my winch is working.....I want to add 4 130w lights to the front of my jeep and 2 on the back and also rock lights
09-13-2007 01:16 AM
Originally Posted by ripbiker13 View Post
Why would you want this?
Winch/Lights other stuff that would run off a bat, and that you dont want to drain your main.

09-13-2007 01:06 AM
RIPBiker13 Why would you want this?
09-13-2007 12:22 AM
HOWTO: Dual Battery Setup

Back in August of '06 I installed a dual battery config in my TJ. Well I finally remembered to post some pictures:

Here's a pic of the "tray":

And of the top cross bar:

And the final product (before reconnecting everything):

Here's a pic of the wiring diagram I drew up:

Shopping list:
- Optima Red Top for main battery
- Optima Yellow Top for all accessories
- Painless Wiring Isolator
- Mean Green 200Amp Alternator
- ~20' of red and 20' of black #2 stranded cable
- a couple feet of 1.5" x 1/8" angle
- a few feet of 1.5" x 1/8" flat
- other: heat shrink, lugs, and wire ties

I set it up with the mindset that everything that came stock with my TJ went to the main battery and everything I've added (lights, winch, CB, etc) go on the accessory battery.

Chose the painless wiring isolator because there is a connection into the cab (not shown on the pic) with a switch that can allow for 1) normal operation where both batteries are being charged, 2) splitting off the Aux battery so it is completely by itself (i.e. not being charged), and 3) connecting the two batteries together in case the main is dead and you need to basically do jump it (with no jumper cables) to start the vehicle.

Uses the stock J bolts to hold it down. The two ends of the cross bar that aren't touching the J bolts are bent at a 90 degree to stop the batteries from shifting side to side.

And I used about 1/2 a can of spray on bed liner to coat the metal cross bar (figured it might make a nice rubberish coating on the cross bar).

In all was a fun project...especially since it was my first.

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