Dual Battery Setups! Let's see them! Multiple Batteries Thread!

I did. Aftermarket switches are way brighter so just connecting them to the dimmer circuit wasn’t enough for me. There’s a big difference between indication and illumination. I already upgraded to meso’s maps/dome so the illumination is well covered.

 

Forgive the brief hijack--Considering a second battery for peace of mind while running aux LED pods and a radio and charging laptop and phone in my first-gen during weekend sleepovers without driving. Each of four lights has a 1amp draw. Doesn't seem like much. Should I do the dual setup or am I overthinking it? If you recommend a dual setup, is a 100ah battery a good pick? No idea which battery brand or if it makes a difference. Thanks!

 

Have you looked at Jackery as a portable battery for aux items? I have a 240 and 2 500s for such things.
I am following this thread to learn, if I ever do consider 2 batteries.

 

Those are pretty cool, but I'm not sure that would be most convenient for me. Do you have them tied to power in your vehicle or do you use them as actual portables?

 

I have just started. Only used it once on a trip to verify the concept.
I do not do serious offroad excursions.

I took a road trip to Colorado from North Carolina earlier this month. Granted it was cold, it did not drain the Jackery much, but it worked great.

I had the Jackery plugged into the 12v truck connection. The Dometic was plugged into the Jackery. While driving, the truck ran it. While in the hotels the Jackery ran the Dometic since the truck was offline.

The Jackery can charge usb also.
I got another 500 because "2 is 1, 1 is none".

 

If you have some power tool batteries an automotive charger is an inexpensive way to diy. I have a dozen 18v makita batteries I use for work. The automotive charger is ~$100 and a

$207 12v 30A DC to DC Charger with MPPT, On-Board Battery Charger for Gel, AGM, Flooded and Lithium Batteries, Using Multi-Stage Charging, Charger for Solar Panel and Alternator, in RV, Car, Marine

12v 30A dc-dc buck converter only $22. I have several old tools I took the battery mounts from though they now sell those too. You can rig the charger to charge multiple batteries either from solar or the running truck but cycle each battery directly through the charger since only the battery actually on the charger gets monitored by it. Jackery is nice but not cheap. Also a 100Ah 12v battery is 1200 watt-hours so this isn’t as much storage as that(my 12 batteries add up to 648 watt hrs). It’s not cost effective by any means to buy power tool batteries for this purpose but if you already have them you already have one of the most expensive parts of a solar system.

 

A marine battery as your second battery will fit your needs nicely. You can get a cheap Walmart deep cycle battery or go all out for an Antigravity lithium battery if you have the funds. A marine battery is a deep cycle battery that has sufficient cca’s to start an engine. So does a lithium battery but at 5X the price.

 

I had planned to go with a marine AGM (something like this: https://www.lowes.com/pd/Deka-12-Volt-800-Amp-Marine-Battery/50183759) until I read some stuff about "dual purpose" batteries not being good at anything and had second thoughts. Thanks for your suggestion.

 

That's not an AGM type.

Advanced Glass Mat batteries are truly maintenance free and are sealed. Also, if you use that one as a starting battery, the terminals will be in the wrong locations.

 

Doh, wrong link. Too many tabs open. Something like this, but prob not this one: https://www.batteriesplus.com/produ...d-boat/deep-cycle/bci-group-31m/sli31dtmagmdc

why are the terminals in the wrong location were it used as a starting battery?

I run a Kinetic agm sound system battery in my old 911 as a starter battery. I certainly appreciate the maintenance-free aspect.

 

For the stock location the terminals have a particular orientation. You could use any battery but you might have to replace the pos/neg cables to reach your terminals.

 

OK, I see what you mean. Mine are on the top, like on these batteries.

 

On top yes, of course. But more importantly, the negative is to the left and the positive to the right. Also the terminals need to be near the edge/corner or the stock cables may not reach.

This is the correct orientation for a stock setup:

 

For what's it's worth I have a reversed 34 AGM as my starter battery. The cables did reach but I rerouted them regardless as I'm making other changes anyway

 

I will be leaving my starter battery as is. My main concern now that you guys have helped me identify the general kind of battery that would be good for me is to find a battery that fits in the space over the passenger wheel well. I won’t make the cables until I have the battery.

 

Jeez, can I even use an AGM battery as a house battery and a flooded battery as a starter? Or do they need to be of the same type?

 

You can, you just need a DC to DC charge controller that can properly charge your AGM house battery. I use a Renogy charge controller and love it.

 

Cool. Which model, and does it sit right next to the house battery?

 

Yes, this is what I'm using:

https://www.renogy.com/dcc50s-12v-5...DPpFfxrpVY_GwX_NRId5m61XPxp9ZyroaAuIoEALw_wcB

I posted my setup in this chat

 

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