Need help with an under hood dual battery setup and wiring

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Gadgetech

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I have a 2022 RAM Power Wagon and I’m installing a dual battery set up to power my needs while camping (fridge, diesel heater, shower at some point and probably something else I’m not thinking of). I really don’t plan on needing to power much else with the set up right now but at some point, I will add some ditch lights as well as lighting to the bed rack to use while at camp. At this point, I’m not ready to consider a power station, but that may be something I add down the road if the power needs exceeded what an AGM battery can provide.

Current plans (with questions) include:
  • REDARC BCDC charger (guessing 1225D)
    • Question: do I need to order a wiring kit from REDARC as well? Looking at the kit recommended for the 1225D it appears that has everything I need. The batteries will sit diagonally across the engine bay from each other.
    • I do plan to add a solar panel to charge the battery through the BCDC at some point.
  • Purchasing an AGM battery
    • What are recommended AGM batteries to buy there’s a lot of room where the second battery goes in my engine bay. I’ve read folks putting a group 31 battery in the Power Wagon engine bay.
  • I want to power things from the dual battery set up in the bed of my truck. Can I just run a cable from the auxiliary battery to the bed with an Anderson connector on it? I read in someone’s post I need to include a breaker or a fuse?
Additional questions:
  • I understand why I might want to use a terminal block, but I don’t understand why I would use a busbar.
  • For things like ditch lights as well as the GMRS radio is it better to wire those to the starter battery or the auxiliary battery?
  • Any recommendations on battery terminal connectors?
  • For connections in the bed of the truck, I’ve thought about building or buying some type of power panel box. Any products or build recommendations?
  • Anything I’m forgetting?
I appreciate everyone putting up with all my questions. I want to make sure that I don’t buy things I don’t need and that I wire the system properly.
 

Dave in AZ

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Redarc bcdc is a good alternator charger.
However, I would not use an AGM as 2nd battery now. An LFP or LiFePO4 lithium battery will give you twice the Watt-hrs for the same weight, and with less hassle for charge-states and battery dying.

I would also consider putting 2nd battery and the bcdc outside of the engine compartment to avoid extra heat there, I'd place in truck cab or bed.

A busbar just makes wiring a bunch of cables together easier than trying to stack on one bolt, if you find you need to power several items from battery it is easier to run power to a busbar then to items. However, I would actually run power to a FUSEBLOCK so each items wire run is protected by a fuse, then you don't need a busbar either.

Buy the bcdc wiring kit.
 

Jason Shelby

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“For things like ditch lights as well as the GMRS radio is it better to wire those to the starter battery or the auxiliary battery?”

On my Jeep (before the wreck), I had all non factory items wired to the auxiliary battery, that way worse case scenario you still have the main battery for all the factory required functions.

And in my case, before the Jeep was totaled it made removal of all the aftermarket stuff super simple.
 
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North American Sojourner

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I agree with the house battery NOT in the engine bay. I run a 8ga wire to my truck bed and use a redarc battery isolator to keep it charged.
I don't have that big BCDC money. Don't need it either.
Zim
 

North American Sojourner

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If installing a house battery in the bed of the truck, why buy that over a Power Station?
Cheaper
Heat is one reason. Heat kills batteries just like cold.
Second, the house batteries are for off road lights, referigator, additional radios etc. You should try to never run accessories off the "truck" battery if possible. Some guy in Detroit in a leather chair designed the truck battery for...................................the truck. LOL
If you want or need the "Power Station" which is another "battery" get one. You'll still have to "charge" it.
Power stations are great for the weekend, maybe a few days without solar. I left the house several years ago. Ahahahahhaha.
Don't forget the switch panel too. That's another several hundo. LOL
Zim
 
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