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

You wouldn't be the first one, it's really just trying to minimize voltage drop works great especially when the Aux battery is in the rear passenger of the bay. The most important parts of the install is proper gauge wire for length, and proper chassis grounding. 4-6ft with 6AWG wire expect in perfect conditions about .08-.1V loss. Nothing crazy, but can be effected by materials, temp, and lots of other factors.

 

thanks for the info. Check out post 3019, thought on the battery placement? Is that okay or should I make the effort to move switch the starter and aux so the aux has more room on the drivers side

 

Unfortunately, I don't think I'm qualified to answer that question. I will leave that to other members who may have more experience with that placement. I will say there are tons of Taco's with batteries in that area, so it must be quite safe if done properly near that line. It would make that BCDC install quite a breeze though!

 

how to say go for it without saying go for it (I appreciate the professionalism)

 

Hello Ryan, I am eventually planning on installing a Redarc BCDC 1225 in my vehicle for a second battery that will be located in the bed of my truck. I just needed some clarification regarding this installation. I have a x2 power AGM battery for my main with a voltage chip to raise the voltage to a consistent 14.5 volts going to the main battery. So going off of the previous conversation, the questions are:
1. Is it best to mount the Redarc in the engine bay and then run the line to the rear of the bed to the battery or mount the Redarc closer to the battery in the rear of the truck?
2. With either mounting point, knowing that I will be running about 15 feet of power cord, what Awg wire should I use depending upon the answer of the first question?
3. I am going to be running a 100 Watt solar set up as well so does that factor into the equation on where it is mounted?
4. For the second battery, I am planning on running either a Deep cycle battery or Battleborn Lithium battery, will the Redarc lessen the cycle life of either of these 2 batteries (Especially the Battleborn Lithium)?

 

I think I read/watched somewhere, that said mounting the DC-DC charger closest to the second battery was best

 

1. It's best to mount as close to AUX battery as possible, this will ensure little to no voltage drop occurs.
2. Best cable size is in chart below for 25amp/40amp options


3. It does not, you can just run your hot cable off the solar directly to the BCDC, ground to chassis.
4. BCDC will most likely improve the life, due to keeping it appropriately charged especially in the Deep Cycles that can be seriously harmed by depletion.

If you have any other questions don't hesitate to ask!

 

@REDARC_Ryan Will the BCDC charge the starting battery through solar if the aux battery is full? I don't recall finding an answer to this but have seen other brands advertised as doing so.

 

Unfortunately, it will not back feed into the starter in order to protect the start battery it has an internal battery isolator.

 

Looking for some info on a dual battery setup.. Was looking at both dc to dc chargers, and battery isolators. Was wondering which is better??

 

DC to DC will be better if you are mixing battery types and/or using solar whereas the isolator will be fine for batteries of the same type and if you have a smaller budget

 

a REDARC bcdc line is both!

 

Dual Battery + Solar set up done. For someone with litterally zero electrical experience prior to this not so bad. For sure the RedArc BCDC25 made this way easier. I would 100% recommend it to anyone who is going dual battery and might one day add solar. It’s really not even that more expensive than buying everything piece meal and a whole lot less wire to run.

Such a cool moment plugging the MC4 connectors in and seeing the solar light turn on. Kind makes me want to put solar on the house, like free energy amazing.

Set Up:
Starter Battery: Stock Group 24
House/Aux Battery: Duracell Ultra Group 27
Battery Trays: Off Grid 4x4
Controller/Charger: RedArc BCDC25
Solar: HQST/Renogy 100W Panel
Fuse Box: Blue Sea 12 Circut

Wiring:
Starter to RedArc: 8 AWG
House to RedArc: 8AWG
House Ground to Frame: 4 AWG
House to Fuse Box: 4 AWG
Solar Ground to Frame: 10 AWG
Solar to RedArc: 10 AWG*

RedArc lives in the glove box. Drilled a hole through the passenger side firewall to pull cables through. Yes there is already a hole but there is a rubber tube coming out of it and it’s a tight fit. Figured it just be easier to make a new one and throw in a grommet that struggle with the tight fitting if I ever need to make adjustments.

*RedArc instructions say 8 but 10 seems fine given the current and it hides better coming down the windshield trim

 

Did that switch come with the RedArc?

 

Doubtful, it looks like a Blue-Sea switch.

 

Hi, I was looking through posts on adding a second battery behind the back seat. Where do you attach your ground?

 

Have heard of people using the seat bolts

 

That switch is not ours, unsure which brand sorry!

 

seat bolts don’t sound like a good idea. They are coated surfaces so you only have the thread for conduction. Probably have to run it to a chassis ground.

 

So is the spot where the battery ground lug is bolted. There are threaded holes all over the rear cab wall as well as under the center console.