Dual Battery/Alternator question
 

Hello all,

Last night my battery light came on, then all the lights, then flashing lights, then no gauges, then.. well you know what happened then. The battery was a 5 month old heavy duty (1000 amp) battery, so I figured the alternator. In a pinch (highway, dark), I managed to buy another battery and limp home. The alternator is being rebuilt at a shop that only fixes alternators and starters as I type, and will be ready in about 30 minutes (brushes worn and one wore through the copper collar, whatever that is).

I recharged and reconditioned my old battery and now have one battery too many. I spent the evening researching dual battery setups, dual alternator setups, and high capacity alternators, but the 50 dollar, one hour, rebuild was too great to pass up.

I am still stuck with the extra battery, though, and I am wondering, has anyone put a dual battery tray is their Disco? Are their vast advantages? If so, is a high capacity alternator a must? Is an isolator necessary? I don't have winches and extra lights, but I don't wallow through mud pits either and that didn't stop me from getting a lift and bigger tires. I'd like to have some extra lights. I am just curious whether anyone has experience with a dual setup and can make any recommendations or tell me what the advantages/disadvantages are?

Best,

Charlie V

you can run two battery, they can be hooked in series similar to a big rig or you can use an isolator.
But without winch and lights and the other crap there is not reason to run two.
Toss one on CL and get some of your money back.
DM has a nice clean dual set up, if you do a search you should be able to find a pic.

Have a look at my recent post.
https://landroverforums.com/forum/di...67/#post421296

Columbia Overland announces our Land Rover Discovery II Dual Battery Tray | Columbia Overland

I've got mine set up with an isolator. One battery is dedicated to my starter. The other is to the distribution block. This way if I leave the lights on or something happens out in the boonies I should be able to get started again.

What I'd really like to do is set it up with a low-voltage relay so that if a battery goes below, say, 9V it automatically opens the relay so the battery doesn't get thrashed ...and brings the other battery on line. But then, I'm probably over-thinking it. I fly jets, which use $10,000 batteries and are difficult to park on the side of the road in the event of a failure or fire. So like I said, I'm probably over-thinking/overdoing it. I also live in CO and really don't want to be stuck somewhere I shouldn't be with a dead battery and/or a crapped out alternator.

You can spend a couple hundred for the redundancy, but a $50 jump box in the trunk is probably a more practical approach.

Careful, that battery tray does not work with 03-04... I've tried. You could probably modify it, but for $150 I wasn't going to make modifications, when I could make something cheaper.

This is exactly what the Smart Isolator does in my link above. Senses voltage and when the starting battery gets to 13.2 it disconnects the soleniod and leaves the house load by it self. When you start the car, the alternator gets the starting battery up to proper voltage, and THEN connects the solenoid back to charge the house... that way you don't get excessive load on the alternator. I've attached a easy to understand PDF that explains exactly how it works.

My case, a dual-battery is required.. the Engel fridge will destroy a battery in no time.
The long deep cycles, always on nature, required me to put a seperate battery.

I did have to drill into the rad support and fab a short arm, but Charlie has a '00 so he's sorted on that front.

Thanks! I'm going to check that out... and I'm also going to stop hijacking this thread.

No!
Well, only if you want to fry every bit of your electronics in the truck. Hooking 2 12v batteries in series will give you 24v.

Hooking them in Parallel‎ will give you a higher reserve capacity.
Ideally, if they are permanently connected they should be of the same type and age. A 5month age difference should be ok.

There are a lot of different methods of running dual batteries and they all have pros and cons. The best way to choose is decide first what your goal is for two batteries, then choose the method that will achieve that goal.
You don't need a higher capacity alternator if you have dual batteries.

Make one like i did. I run them in PARALLEL. I run a yellow top and a blue top. They are always connected in parallel and im using the stock alternator.

https://lh3.googleusercontent.com/oV...=w1299-h974-no

https://lh3.googleusercontent.com/iR...=w1299-h974-no


https://lh3.googleusercontent.com/tD...=w1299-h974-no

you are correct I misspoke (as the politician say) it is PARALLEL not in Series.
but to your back to your OP unless your running a winch or ton of light there is no need.

Or Fridge that is always on