PDA

View Full Version : Dual Battery Wiring



4.3LXJ
10-24-2009, 05:33 PM
I have already had one request for a wiring diagram for dual batteries that can be isolated. Below I have included a wiring diagram that allows you to isolate the batteries, hook them together and charge them, and use the second battery as a jumper if you run the primary battery down. It is all very painless. Whenever you turn on your ignition switch, the batteries will be hooked together. Turn it off, they are isolated. You can run your accessories and drain the secondary battery and not touch the primary. Start your engine and the secondary battery will charge. Just about idiot proof. If your primary battery dies because you left your lights on in the fog, flip the switch and instant jumper cables. Start the engine and it will charge the low battery. The solenoid in the middle of the batteries that connects the two positive posts is a continuous duty 250 amp solenoid. They generally have to be ordered. A relay is used to power the solenoid to take the heavy load off the ignition switch and auxiliary switch. Cable in these photo is 0 gage stranded copper.

http://i649.photobucket.com/albums/uu215/warriorsuspension/DualBattWiring001.jpg

The battery connections were made cleanly with aftermarket battery terminals pictured below.

http://i649.photobucket.com/albums/uu215/warriorsuspension/IMG_0274.jpg

All connections were painted with a product called Electrical Tape sold at hardware stores

BlueXJ
10-24-2009, 07:16 PM
Thanks just what I needed to see.

warrpath4x4
10-25-2009, 12:14 AM
i am planning on doing dual batteries in the week or two. i have a marine dual battery switch from another project, i can charge/use battery 1, battery 2, or both.

gistecknician
06-05-2010, 08:11 PM
This is a really useful diagram. I will definitely be running this setup as I expand my electrical accessories (winch, aux lights, etc.)

Thank you

ndblack3893
06-30-2010, 07:13 PM
I can't see the diagram or the photos? What am I doing wrong?

Mudderoy
07-01-2010, 02:34 AM
I can't see the diagram or the photos? What am I doing wrong?

I don't know. The guy right above you is new also and apparently he could see it. I suspect the problem is on your end. You might want to reboot your computer, slap it around, etc... and try again.

Kimber6331
08-05-2010, 08:36 AM
Whats the benefit of running two batteries?

96xj
08-05-2010, 09:25 AM
http://i649.photobucket.com/albums/uu215/warriorsuspension/DualBattWiring001.jpg


i see RED /YELLOW are you using 2 different batteries ?
and do you got a pic of your set up i would like to see where you got the 2ND battery sitting

4.3LXJ
08-05-2010, 09:37 AM
They are right next to each other in the back cargo area.

modestmar00xj
11-30-2010, 12:20 AM
awesome man! just what i needed to see!

PolarXJ
12-17-2010, 02:39 PM
Where did you pick up that battery terminal with the two crimpable ends?

4.3LXJ
12-17-2010, 06:47 PM
I bought them at NAPA. They come in two styles, crimp and solder.

4x4Dalton
12-17-2010, 07:01 PM
Thanks man been thinkin of doin that later on. Thanks for the pic and info on parts and hook up as well.:thumbsup::thumbsup:

PolarXJ
12-21-2010, 02:23 PM
I just upgraded my battery cables to 1 awg during my engine swap, and must have missed those or my local napa didn't have them.

4.3LXJ
12-21-2010, 04:20 PM
I had to order mine. Tell them to look in the books.

Gabriel J
01-17-2011, 03:04 PM
How bout placement location?:thumbsup:

4.3LXJ
01-17-2011, 03:53 PM
Mine are in the rear cargo area. I don't have enough room for even one battery now with all the stuff under there.

Gabriel J
01-17-2011, 11:48 PM
Nice... Not to hi-jack your thread.. Since you have the 4.3L... I thought you would get a kick out of this.. a friend of mine that goes by CheaperJeeper on Pnwjeep.com is building a 4.3L Diesel powered XJ... I have seen it and its friggen trick!!! Will when finished run all Bio-Diesel....:thumbsup:

j&d Greens
01-21-2011, 03:57 AM
When you up-grade to two batteries would you need to up-grade your alternator as well? or would it just be a good idea to anyway????

4.3LXJ
01-21-2011, 10:40 AM
It never hurts to upgrade the alternator for four wheeling, but it is not necessary. Mine is a stock 100 amp

j&d Greens
01-22-2011, 10:31 AM
It never hurts to upgrade the alternator for four wheeling, but it is not necessary. Mine is a stock 100 amp
Thanks, I think before we go to two batteries, we will up grade the alternator (we will know it is new and dependable). That should allow us to run the lights on the safari rack when we need them, then we will look into two batteries set-up.

modestmar00xj
01-22-2011, 10:57 PM
does anyone have a picture of there dual batter set-up?

BrianXJ
01-22-2011, 11:02 PM
I would like to know more about the mounting locations as well. Curious to see how you hold them down incase of rollover.

4.3LXJ
01-22-2011, 11:29 PM
I don't have a pic right now, but I made a tray out of angle aluminum and bolted it down behind the rear seat with the solenoid in between and then used standard J bolts and battery hold downs.

BrianXJ
01-22-2011, 11:34 PM
ah sweet kinda what I was thinking

LizardRunner
03-31-2011, 01:37 PM
great info and diagram. I have been thinking of putting two batteries in da lizard, mounting them in the seat well of the back seat (taking out the bottom of it since I don't ever have the thing in the riding positon anyway). This info will be very handy when I get to this project.

MudRaider
11-08-2011, 05:46 PM
That is a great diagram. Definitely gonna save that!

4.3LXJ
11-08-2011, 08:56 PM
You can simplify that if you want. But that has all the bells and whistles

DirtBound Offroad
11-12-2011, 10:57 AM
I ditched my stock air box and made a second battery bracket, that bolts to the factory holes so smog time I can swap the box in.

I used a isolator and not a solenoid, at times i wish I did as the starting battery does occasionally go flat. It sure would be nice to flip a switch and crank it, I might add one later on just for that.

I can jump myself with a 1ft of wire though so not a but deal.

http://farm6.static.flickr.com/5065/5886076622_0e002e2cc4_z.jpg

Marsbar
11-16-2011, 09:35 AM
I have on all my 4wd's for the last 25yrs used a system of using the constant rated 200amp solenoid to do job, but have always wired the positives of both batteries together.

The reason I do this is when switching positives, arcing across the solenoid contacts can course a voltage spike that can damage electronic equipment. I also use a push button switch & pick up the positive feed from the second aux start battery to activate the solenoid when the start battery has been flatten. I never use the aux start battery to power any equipment so I only use a small battery(33amp SLA/AGM, tho it's big enough to boost start).
Because its small I can custom mount it just about anywhere in the engine bay & they can even lay on their side(SLA=Sealed Lead Acid-Valve Regulated). I have always custom made the mount for the main starting battery & used a bigger size than standard.

I have two 75amp Aux Deep Cycle Gel batteries mounted in the back of my truck to run the frig, inverters(1x300w, 1x600w), laptop, multi-media system, 2TB Hard drive with all my movies + LED worklamps etc & wire them in the same way(switch them using the negative/earth).

I couple them into the system via 50amp Anderson plugs so I can remove 1 to run the frig back at camp & I charge the other while I'm wheeling, These batteries have the same setup of switching the negitives/earths & any accessories I'm running off them are wired above ground so wont draw any power from the main starting or backup aux start batteries.

All this might sound difficult but its not rocket science but it isn't

93xj97347
10-06-2013, 03:09 PM
I'm putting in a second battery in the back of my jeep. Can I hook the ground to the body or do I have to ground it to the motor? I have upgrade my grounds to the body already.

4.3LXJ
10-06-2013, 04:53 PM
You should ground to the motor and from there or a second ground to the body

93xj97347
10-06-2013, 06:55 PM
Thanks for the help. Its all hooked up and working fine so far. Now I finally get to hook up a few things. Amplifer, overhead lights, inverter, and I'll have a place to hook up my compressor.

4.3LXJ
10-06-2013, 09:20 PM
Have fun with the new goodies

RRXJeeper71
01-02-2014, 09:45 PM
I was really asking if any of the dual battery wire kits(solenoids and wires/switches) were worth the $$
I am more keen to buy it all together than piece it together myself
Want to see some pics of all those that have a dual battery system installed!!!

4.3LXJ
01-02-2014, 09:52 PM
http://i649.photobucket.com/albums/uu215/warriorsuspension/IMG_0911.jpg

The isolator continuous duty solenoid is in the middle. Much cheaper than the kits

mudslut
01-03-2014, 07:58 AM
4.3 xj knows his shitttttttttttttttttttttttttttttt............thank s man good thread

mudslut
01-03-2014, 08:08 AM
http://i649.photobucket.com/albums/uu215/warriorsuspension/IMG_0911.jpg

The isolator continuous duty solenoid is in the middle. Much cheaper than the kits

looks like a old ford starter solenoid like I use on my xj:patriot:

4.3LXJ
01-03-2014, 10:12 AM
looks like a old ford starter solenoid like I use on my xj:patriot:

Yes, only it needs to be continuous duty. The typical starter solenoid is intermittent duty

OneArmArrowSlinger
01-30-2014, 10:57 AM
Awesome diagram! Exactly what I been looking for, thanks

93xj97347
02-01-2015, 06:13 PM
I'm about to rework all the wiring in my jeep to get all the extra wiring out of the interior. I'm going to be upgrading my alternator and moving the second battery to the front closer to the winch. Right now both my battery's are wired inline and i want to isolate them. I have a 200a solenoid on the way but I need to know what size relays I need to use

4.3LXJ
02-01-2015, 10:32 PM
If you follow my diagram, the standard 40 amp little black boxes are all you need

93xj97347
02-01-2015, 11:19 PM
Thanks. That's what I needed to know