Dual Batterys

[FordTruck]

Has anyone ever had dual batterys on their truck?
How would i go about hooking up the dual batterys,how do they both charge? My plan is to run one battery for all the stuff on the truck like how it came from Ford,and using the second battery for my extra lights, radio and CB because my equipment will use alot of juice (with my linear and stuff). Just wondering how i could do it any help?

[fmartin_gila1]

You need an Isolator setup. NAPA or most any RV place should be able to sell one.

Fred

[kaptnkaos]

The battery isolator switches the charge from the alternator to which ever battery is the lowest.
The cable that normally goes from the alternator to the cylinoid is split, you'll wanna put some good ring ends on the cut wire.
The wire from the alternator goes to the isolator feed terminal, the second wire that goes to the cylinoid goes to one of the output terminals.
That will charge the primary battery.
A wire from the (+) side of the aux battery goes to the other isolator output terminal.
A ground wire on the aux battery needs to be attached to the frame or engine to complete the circuit.
The isolator should have a wiring diagram w/instructions with it.
An isolator runs between around $50-$80 depending on the brand.

That's how my '68 CS is set up.
Right now I don't have the aux battery in the truck. On my camper it goes in a battery box inside the camper.
Before I use it again, I'm gonna set it up to be under the hood.
It's just a matter of running a new wire from the aux battery to the CS plug in on the frame, for some reason I'm not getting any power at the plug.

The most difficult thing I ran into was finding a decent driver's side battery support.

KaptnKA S

[Fordlorn]

I had a Chevy that someone had put dual batts. in and they did it themselves. Was a very nice job. They used a starter solenoid(or two, I don't remember) to isolate the "other" battery from the main battery when starting, that way the "other" battery that might be ran down because you used 12V lighting in your camper or what not would not try to "steal" the juice from your starting batt.. Then as you let off on the key the other batt. is cut into the charging circuit and gets charged. I saw a wiring diagram on another sight but didn't save it. Sorry, I'll do better next time. Find the info you need and do it yourself, you'll be much happier and wealthier too. Besides then you can brag about how you "did it myself" too.

[kaptnkaos]

Hey Jake...

How does that work with a deep cycle battery ???
If you are running your camper off of the battery, it will need to be charged more than the primary one will.
If you hook them both "hot all the time" wouldn't that put an overload on the alternator trying to charge both batteries without an isolater ???
I had the duel battery set up with an isolater with my old camper for several years...
I never had any problems with it at all.
I'm not arguing, just curious.

KaptnKA S

[kaptnkaos]

Jeez. you really want me to write a book on this.

Hey Jake,
Thanks for your response...
While it might be "common knowledge" to you, it isn't for the majority of us.
Information like this isn't "general information" so your input is appreciated.
Please don't "talk down" to us when we ask questions.
Just because we don't know the same things you do, does not make us stupid.
Do you know a supplier for that style of solenoid ???

I also like things that are simple and have less chance of failure.
If the setup you described works better and has less chance of failure, I'm interested.
The way the camper I have now is set up, I have to take the battery out or run an extension out to the camper and charge the battery manually.
Then it is only good for a couple of days... the PO had 2 batteries for it, but he kept one and the other went bad last winter so it was replaced this spring.

KaptnKA S

[bluef250]

This is my opinion and experience with dual batteries. I really, really hate battery problems. When living in Phoenix, I was lucky to get 4 years out of battery. The heat kills the battery. Here, I generally get 5 to 6 years.

I use a boat mechanical switch.

http://cgi.ebay.com/ebaymotors/High-Out ... enameZWDVW

The switch positions are "off", "1", "2", and "both". Each battery "+" terminal is attached to a separate post on the switch. The third post is attached to the starter solenoid. The battery ground ("-") terminals are attached to the engine block. This system has worked well for me for more than 15 years. I keep the switch in the "both" position most of the time. If you were camping you could run one battery and use the other for starting. I have a stock alternator and it will charge both batteries as needed. If one of the batteries is down, it just takes longer. This is really no different that jumping a dead battery. If I am working on the truck, I turn the batteries off so I don't have to remove the battery cable. If I suspect a battery is going bad, I run on the other. To run like this, I feel you need matched batteries (as much as possible.)

I believe different batteries from different companies are built differently. Some have more surface area on the plats, some have different chemistry (gell cells are different than wet cells, etc.) The deep cell batteries may have the most plats and may have more electrolyte. Some companies have better quality control, some worse. I think all the 12 volt batteries have 6 cells and run with about 2.2 volts per cell and, when new, should work if they have enough power to start the truck.

I have a design for the dual battery setup using standard relays that uses 2 starter solenoids, allows dual charging after starting, allows selection of both, battery 1, or battery 2, and off, but haven't built it yet.

[Jake11]

I say what I know, no offense meant. Do whatever you like.
Jake

[olgreen69]

i just put in an optima yellow top. doubtful of its claims i tried to kill it. so i hooked up my power inverter plugged in a box fan and my laptop, with the radio blasting and tooled around on the interweb unitl i got bored. unplugged everything turned the key and on the first crank she started right up. so if your just running lights and a cb, i wouldnt worrie to much about dual batteries. just get one really good one. thats my

[rjewkes]

and even at that when running you should be running off the alt and charging the battery.

so what about the 100 amp alt and wiring/volt reg from a 92 Econoline? One upgrade i may do while i have the sport custom appart for cleaning and dropping in a donor engine.

[olgreen69]

How easy is the swap, because I've been meaning to clean up some electrical under the hood. And that would be the perfect time to tell my banker/ wife that I need a new alt.

[gbrett]

I have dual batteries in my bronco what i did was get a constant duty solinoid and run the 2nd battery through it as an isolator the solinoid is powered in the run position so as soon as i shut it off my batteries can not drain each other but I also have a switch so i can turn my aux battery off anytime I want to