Anyone running 3 batteries?

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What is the best way to hook up 3 batteries?
Starting single battery and then 2 aux batteries to be used for fridge, camp lights and inverter.

I was thinking of doing this:

Power management charges the staring battery and the front aux battery (which is connected to the rear aux battery).

I am thinking to use the Slee tray for the front Aux battery and then put the second aux battery in the rear of the vehicle some where.
Run a large cable (think I have a Marine 1/0) from the front aux battery to a breaker upfront, then to the rear to a second breaker, and then connect to the rear aux battery.
The primarily connect the rear aux to the Fridge and inverter.

Is there a better way to do this? or someone see an issue with hooking them up this way?
 
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Not sure what charging component you're using but check out the bottom of this page, they reference a component you can buy that will tie in multiple batteries. ML-ACR Automatic Charging Relay with Manual Control - 12V DC 500A - Blue Sea Systems

That said, does Redarc provide an out of the box solution for multiple batteries? Think they are probably a better option since the alternator isn't what's doing the charging directly.
 
I am running 3 35 series Oddessy Batts. I’m using a perfect switch solid state isolator. I run two batteries together for my aux side and my main is 1 batt.
When car is running, it charges all 3 batts. When car is off, the fridge etc draws down aux batts and never touches main batt. Also, when car is off, solar charges all 3.
If need be, I can combine batts to jump start car.
Scott at Perfect Switch is amazing resource for multi-batt setups.

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Pretty simple, just use any existing dual battery system that is commercially available and run your two aux batteries in parallel. If budget allowed I'd use one of the following:



I had a small budget for my dual battery setup and used the T-Max setup from Amazon.
 
I echo the question...why 3 batts?

There's much more complexity here than would meet the eye. It's not just wiring them up in parallel, isolator, feed them a power source, and all is happy.

Batteries in a bank need to be wired such that they are drawn and charged in a balanced fashion. That's almost impossible to do with 1 part of the aux batt in the engine bay, and the other part in the cabin. Otherwise, there will always be microcurrents between them as they fight to balance themselves and support a load - e.g. premature wear.

Each bank needs it's own charge controller. A single charger (e.g. alternator) cannot charge multiple banks at different states of charge.

The charger needs to match the battery chemistry. OE alternator is designed for flooded.

There's more here, but some of the core basics.

You didn't mention solar. Perhaps that's one of the (better) ways to support energy demands than just rely on battery reserves?
 
Look into running one Lithium instead of two conventional batteries. Same capacity, 1/4th the weight, half the footprint, accepts charge faster (usually).
Working on a setup now with a ReLion lithium battery (great service from them) as the second battery. What are you think @TonyP? Glad you are considering.
 
Working on a setup now with a ReLion lithium battery (great service from them) as the second battery. What are you think @TonyP? Glad you are considering.

I ran a Battleborn 100aH for a while. Big fan of Lithiums. The same battery will be going in the Troopy. I might even add another since they're so lightweight, I'll have tons of extra room and this rig will be set up for long travel.
 
I ran a Battleborn 100aH for a while. Big fan of Lithiums. The same battery will be going in the Troopy. I might even add another since they're so lightweight, I'll have tons of extra room and this rig will be set up for long travel.
A long travel Troopy? Or a Troopy that travels for long periods of time?

PS. me love you long time.
 
I am running 3 35 series Oddessy Batts. I’m using a perfect switch solid state isolator. I run two batteries together for my aux side and my main is 1 batt.

What did you use to hold down the 2 batteries on the driver side? Looks like a really nice setup.

I have been running 2 batteries in another vehicle of mine, but 1 aux battery will only last 2-3 days with the fridge.

Thanks for all the other pointers and reply's.

I'll take a look a the lithium. The lithium said good for 3000 charges but pricey.

My charging system is exactly like the deep sea version, mentioned above. After the engine starts the batteries are connected in parallel, and then when I park and camp they are isolated. I have a manual override if needed to connect them.
 
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Umm...

Edit: probably the wrong spot for this but it was the most recent battery related thread.
 
If parked my 100w panel is more than enough to keep the house battery up. I'm sticking with just 2 batteries. Perhaps an evaluation of your power consumption might help.
 
I’m running three batteries:

  1. Stock battery
  2. Goal Zero Yeti 1000 Lithium
  3. Anti-gravity xp-10 lithium jumper

Less than 50lbs of additional weight from stock.
 

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