Dual Batteries

It all depends on your needs and budget (sorry there is no easy answer)

I have a TJM IBS system.

It isolates the batteries when the alternator is not charging, leaving the main battery untouched at this time, I have connected all accesories to the 2nd battery, therefore only being able to flatten it while leaving the main battery charged. However, the interior and headlights still run off the main battery.

You could set it up so that everything except the starter runs off the 2nd battery, this would work for most vehicles, but in a diesel "if you get no glow there's no go" to get around this would require more brains than i have.

When the alternator is charging the IBS keeps the batteries isolated until the main battery is fully charged, then it will begin to charge the BOTH batteries together, it continues to monitor the main battery, if it drops charge, it isolates again and gives priority to the main battery.

I do like the option of being able to join the batteries together, this has saved me a few times when the battery was on its way out. I also like the ability to check the charge level of each battery and of the alternator.

I used to believe that a starter and a deep cycle was the go, now i use two exide extreme batteries which I believe give me greater flexibility.

In terms of where to put the batteries, you can get all manner of cradles, I went with a double cradle from Pirahna, as my original cradle collapsed (and shorted out the loom starting a small fire in the steering column (that was fun)).

Enjoy making the decision, no one can tell you what is right for you, but the above sysytem suits my needs right now.

cheers

Kempy,

I have just gone through this exercise. Of the 4wd suppilers I found Pirahna to be the most helpful. I then spoke to my local auto electrician and he has done hundreds of them. You will need an "isolator". This device stops current being drawn from the start battery. Modern isolators work automatically so there is no chance of flattening your start battery. Your second battery will be of the "deep cycle" type which is designed for prolonged slow release of current. Depending on how easy it is to fit to your car, the type of isolator you choose, the capacity of the deep cycle battery, whether you want gauge inside the car, how many power points you want fitted etc budget on somewher between $650-$1000.

Regards,

Jim.

Have a chat to another auto elect. You should be able to install the isolator youself along with a switch to the inside of the vehicle so you can control the isolator.
The main component is a 100 or 120 amp starter relay which costs approx $60.

the entire install should cost under 200 including the battery tray. but excluding battery.

Brett

I did it as cheap as I could kempy, did the work myself, got an ARB tray for about $85, isolator cost about $120 ( a Redarc voltage sensing one, with soime type of transient spike killing device within), and I got the battery for nothing, same as my starter battery, from a friend.

Still cost me over $200 without the battery or cabling costs. Its an easy fit but you need to have some cool tools.

All the best
So many places to go!
So much work to do :0(

Kempy, I also have a Troopy, and it came with a dual batt. tray but no system per se in it.

The cheapest ans simplest way to do it is as a few other have said.

You need,
a Dual battery tray ?? Whatever ARB charge or buy 2nd hand from wreckers
100-150 Amp Solenoid about $80-120
switch - bugger all from dick smith etc.
Cable - GEt BIG CAble 35mm2 at least

A slight improvment on that is to also get 2 1 amop diodes, and take power off both batteries via the diode to run the solenoid contacts, than it doesn't matter if EITHER battery is DEAD, then the solenoid will kick in. Wire it to the ON power from the power box under then bonnet so it only come on when the key is in the ON position (or ACC if you prefer)
Simple, takes about 3 hours to do, and is fool proof. It doesnt have the voltacge sewnsing and charge equalisation stuff of the Piranha etc, but it also wont fail or play up!

If you want you can email me and I'll send you pics and detailed info of how I did mine.

If you want to install a deep cycle and a standard crank batt you may find they last longer with a regulator system, I have 2 exide N70ZZ HD 700CCA and replace one of the batteries every 2 years or so

PS when you install the second battery tray, make sure the aircon pipe off the compressor doesn't rub on the tray. It is often a tight fit, and can cause loss of gas from the aircond.
Shaun C

Kempy,
I made up my own battery bracket out of bits and pieces. Bought a new 700cca 17 plater Desert King battery for $130 and a Rotronics MH10 Battery isolator for $250. Installed my 4 year old Yuasa Overlander 700cca as the auxilliary battery and connected the batteries with jumper lead cables $10. The system works well.
Cheers,
Willie
Never a dull moment

Check out under the bonnet for any boxes etc that have any of the brand names mentioned above. I'd then go to a local auto electrician and get him to check out what you have and how it is set up.
You probably won't get charged too much for this service, it may even be free if you need to get your system altered.