Talk to me about 2nd batteries (1 Viewer)

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I approached dual batteries (both AGM) in my 100 a bit different using a simple 500a solenoid as an isolator.

The isolator is triggered by a two pole (on-off-on) switch inside. On one pole the relay is triggered via 'ignition on'. This is pretty much a set it and leave it setting. The batteries are separated when the vehicle is off. The 2nd pole is connected to the 2nd battery so that I am able to manually activate the solenoid to self jump start. The self jump start worked great one day in the shop when I managed to drain the starting battery. Not only is the system simple and dumb, it would be very easy to repair it in the field if necessary. It's been working for the past 3-4 years.

A couple of years ago I also added 100w of solar to the roof and use a basic solar charge controller to help keep the 2nd battery topped off when parked.

is one a deep cycle agm and the other for starting?
 
is one a deep cycle agm and the other for starting?
They are both standard starting type AGM's from the parts store. The starting battery is a H7 and the house battery is a H5.
 
I ended up going with the Ironman Dc to DC charger with solar (it’s discontinued now, more on that in a second) and it seems to be working great. I have the regular start battery which is lead acid and the Optima Yellowtop in the slee tray.

Regarding Ironman charger….it was listed as new a few months ago when I ordered it. Seems well built, but I called them about connecting solar panels. I figured it would have come pre-wired with solar panel connectors, and asked which ones I should order. I also advised that I was concerned they had removed them from the website and asked about that.
Ironmans response was that the charger works great, but the connectors weren’t included (also for their dual battery monitor) and that everything would need to be hardwired connected on my own. It wasn’t their intention, but it’s what their supplier sent them….
And because of that, they told me they were refunding the entire purchase price of my charger and allowing me to keep it. Crazy!

So, I’ll still need to figure out what type of connection to use for solar input (I want to be able to connect and disconnect as needed) and hardwire (or find a connector) for the dual battery monitor.

Overall I’m happy with the charger so far. Haven’t tested it in the field yet, but all indicators and voltage readings show that it is working as intended.
 
I had two AGM batteries in my dual set up. I don't think the AGM charges properly off the alternation, even with the alternator booster installed. You have to put it on a plug-in smart charger to actually top it off. I was never happy with the set up. So I switched to a regular starting battery and a DC/DC charger and a LiPo house battery. I really like this current set up. I have a true 100 amp hours on the LiPo battery and I don't have to worry about any funky charge patterns for the starter battery. It's what the alternator was designed for. Just my take, having been through a about three or four different set ups.

Also, the LiPo battery weighs virtually nothing compared to the AGMs. And I got the one that has an internal heater, so it should still charge when it's stupid cold out. Need that for my electric blanket!!
 
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I ended up going with the Ironman Dc to DC charger with solar (it’s discontinued now, more on that in a second) and it seems to be working great. I have the regular start battery which is lead acid and the Optima Yellowtop in the slee tray.

Regarding Ironman charger….it was listed as new a few months ago when I ordered it. Seems well built, but I called them about connecting solar panels. I figured it would have come pre-wired with solar panel connectors, and asked which ones I should order. I also advised that I was concerned they had removed them from the website and asked about that.
Ironmans response was that the charger works great, but the connectors weren’t included (also for their dual battery monitor) and that everything would need to be hardwired connected on my own. It wasn’t their intention, but it’s what their supplier sent them….
And because of that, they told me they were refunding the entire purchase price of my charger and allowing me to keep it. Crazy!

So, I’ll still need to figure out what type of connection to use for solar input (I want to be able to connect and disconnect as needed) and hardwire (or find a connector) for the dual battery monitor.

Overall I’m happy with the charger so far. Haven’t tested it in the field yet, but all indicators and voltage readings show that it is working as intended.
I have a RedArc with solar inputs and hardwired Anderson connectors with a weather boot. At camp I connect it up to a solar suitcase.

full


full


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Oh nice! I like that mounting location.
Links to that connector?
Here is what I bought from Powerwrex.

SB50 SB Series 50 Amp Anderson Powerpole Kit (Color: Gray, Gauge: 10)SB50-10-GRY8
SB50 Environmental Boot with Cover, Source Side3-6055P22
SB50 Environmental Boot with Cover, Load Side3-6054P22
5915-BK Anderson Power SB50/PP75 Powerpole Contact 10/12 AWG5915-BK8
 
That's super neat install. I might copy that as I currently have a spare anderson with a volt meter built in just flopping about in the engine bay.
 
With that arrangement, how big are those fuses running from the Aux to solenoid to main batt? I've wanted to setup mine in a similar fashion, but fusing it to any functional degree seemed likely to also prevent the current needed to jump start. 🤷
Whoa.. super late reply.. just saw this post. Currently the Aux batt has 100A fuse to the Redarc Solenoid for Jump starting... and also a 100A Fuse at the Main Batt as well. No problem jumpstarting w/ the push of a button from driver seat. Love it. Used it a several times already when my Main batt was getting old. Switched out to an Odyssy Extreme Grp 31 for Main Batt now... and never needed jump start since~
 
Ironman 4x4 has a new dc to dc charger 40 amps.

I think it’s currently 25% off. May go for that one!
I initially started w/ the Ironman 40A DCDC charger... and their Jumpstart Solenoid.
Until it caught fire.

Long story short, the IM DCDC Charger worked fine, however their Jumpstart solenoid was a poor design.
The mounting rivet on the base is at the same plane as the Hot lead (+) lug on it. One day I was washing my LX and hosed down the engine bay.
Later smelled something burning... and saw smoke come out of the IM DCDC charger, where the wires exit out of the case.

I immediately pulled the fuses to disconnect the Main batt from the Charger. Thought it was ok, but several minutes later saw smoke again.
This time I could see a small flame inside the IM DCDC casing. Used a fire exinguisher to put out the little fire inside.
I also pulled All power off of it, and pulled the components out. Saw tell-tale signs, and basically there was water on the solenoid base, shorting out a power wire to ground (via rivet)... and it was shorting something out in the DCDC Charger. Crazy to think what would have happened if I was on trail and went thru a water crossing...

Luckily no damage anywhere else besides the IM units. IM also refunded me the cost of the DCDC Charger and Solenoid.
Moved onto Redarc ever since... Should have gone this route from the beginning. Solar Panel hookup was super easy too.
Redarc DCDC will charge the Aux Batt w/ solar until it's topped off, then charge the Main batt w/ solar.
Sitting between trips, no more worries of batterie's being charged.

IM Solenoid.jpg


IM Solenoid1.jpg


IM Solenoid2.jpg
 
Redarc DCDC will charge the Aux Batt w/ solar until it's topped off, then charge the Main batt w/ solar.
Sitting between trips, no more worries of batterie's being charged.

Interested in having this capability. How did you wire this up and what Redarc did you use?
 
Interested in having this capability. How did you wire this up and what Redarc did you use?
Im running a Redarc BCDC1240D... I wanted to have 40A charging capability... but most common chargers are the BCDC1225D (25A charging).
They are Solar ready (MPPT controller built in)... just hook up a raw solar panel straight to it (In my case I use a BougeRV 100w Panel).
Jump start is handled by Redarc SBi12 Solenoid.

From what I understand, is the "D" at the end of the model name is for Dual... meaning it will charge the Aux Batt first (from solar), then charge the Main Batt next, once the Aux is topped off.

Its a great reliable Install it and forget it unit.

redarc.jpg


redarc sb112.jpg


Redard diagram.jpg
 
Im running a Redarc BCDC1240D... I wanted to have 40A charging capability... but most common chargers are the BCDC1225D (25A charging).
They are Solar ready (MPPT controller built in)... just hook up a raw solar panel straight to it (In my case I use a BougeRV 100w Panel).
Jump start is handled by Redarc SBi12 Solenoid.

From what I understand, is the "D" at the end of the model name is for Dual... meaning it will charge the Aux Batt first (from solar), then charge the Main Batt next, once the Aux is topped off.

Its a great reliable Install it and forget it unit.

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And they make a 100 specific mounting bracket, that mounts behind the front grill!
 
And they make a 100 specific mounting bracket, that mounts behind the front grill!
Yes they do! Should be keeping it nice and cool there too.

I chose not to go that route mainly because things already felt cluttered up front,
and also didnt want to block more air than I already was... (winch, stacked coolers, etc)
 
Im running a Redarc BCDC1240D... I wanted to have 40A charging capability... but most common chargers are the BCDC1225D (25A charging).
They are Solar ready (MPPT controller built in)... just hook up a raw solar panel straight to it (In my case I use a BougeRV 100w Panel).
Jump start is handled by Redarc SBi12 Solenoid.

From what I understand, is the "D" at the end of the model name is for Dual... meaning it will charge the Aux Batt first (from solar), then charge the Main Batt next, once the Aux is topped off.

Its a great reliable Install it and forget it unit.
I’m using the BCDC1225D and I don’t think it or the 1240 have trickle charging of the starting battery. In fact I think I proved it the last time I boondocked for four weeks and then had to do a jump start! Pretty sure the “D” is just for dual input (solar plus alternator) and I can’t see anything about starting battery charging in the manual. I’m probably going to add an independent solar trickle charger unless someone knows how to get this with the BCDC
 

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