battery mounting

[DaveL]

Just bought two AGM deep cycle batteries for my 21RBS CampLite.  Was planning on removing the existing conventional lead acid from the tongue and mounting the two AGMs under the bed area.

- should I buy a polypropylene housing to put them in versus leaving them "bare"?  The AGMs are about 100 lbs a piece so getting them off the tongue would be a benefit.  Plus they are a size (bigger than 31's) such that a standard inexpensive battery box wouldn't work outside ......  would have to use a "toolbox" type.  I have found an Atwood 9084-1 which would accommodate one battery except height; they are reasonably priced at $21 each that I could make work inside.

- For under the bed, I was thinking about just mounting a piece of angled aluminum directly to the floor at the base to anchor and maybe a strap to the side to hold them in place.  Should I put down a rubber mat or insulator rather than letting them rest directly on the aluminum?

[Merlin]

Those are big bad boy batteries (BBBBs)! What size battery weighs 100 lbs? Most folks mount things like batteries outside to save valuable storage space inside. Since they are AGM, you do have the choice to mount inside. I like the battery box you linked to. It would help secure the positive cable connection from shorting out (if you use the lid) and provide a convenient and potentially strong fastening system. With those, you would not need to worry about a rubber mat under the batteries. My #1 concern by FAR is making sure you mount them securely. You REALLY don't want 2 BBBBs coming loose inside the camper and it's a rough ride. I mounted my 2 AGM batteries in a toolbox on the tongue and like the arrangement. In particular, the battery circuit-breaker/off-switch is easy to get to out on the tongue and my dual axel 16TBS needed the tongue weight. And the toolbox stores all the electrical cables/extensions/adapter for shore power.

[DavidM]

What battery is bigger than a Group 31 and 100+ lbs, a 4D, an 8D?

AGMs don't really need battery boxes, but I would strap them down and as you note, put some angle aluminum pieces down to keep them from sliding.

And what is your tongue weight that you need to reduce it by moving your batteries aft?

David

[DaveL]

These are Hitachi CS3   HRL12540w FR.....  They measure about 13  1/2" long, 6 3/4" wide, and 11" high.  134 AH each.  Got them off Facebook Marketplace as used.  Cell tower service guy had them.  They are date stamped 2017.  Spec sheet says they have a 10-12 year service life.  Passes load and capacity tests.  Paid $60 each for them; they go for $300 - 400 new.  I figure that even if they have reduced capacity it is still a lot more than the 27 battery I have now (70 AH) and should be great for several days of boondocking.

The guy home bases out of Rutledge, Ga (about an hour east of Atlanta).  Seems to have a lot of different size AGM batteries.  Travels a lot.  Had to wait until he passed through to Birmingham to pick them up.  Seems to service the Southeast.  This was the best deal for the amount of capacity.  In hindsight I might should have gone with more multiples of smaller sizes so that I could mount them in readily available boxes.

Back in my ham radio days we would routinely buy these type batteries surplus for VHF repeater back up power.  Spec sheet says they weigh 96.76 pounds.... so may have exaggerated a little saying they were 100#.

Sounds like no one disagrees that I can probably just mount them on the aluminum floor under the bed as long as they are secure and I protect the positive leads.

Thanks for the advice.

[DavidM]

I don't think those batteries will fit in any of the commonly available battery boxes- too long and too tall. But mounting them on the floor inside the bed frame should work fine.

That will definitely lighten up your tongue, so be careful about it getting too light.

David

[Nealcrichard@gmail.com]

Go on amazon or etrailer and look up Noco or Camco battery boxes.  They have all sizes.  I am preparing my tongue to mount a 4d sized 200ah lithium battery today.  Bought a small sheet of aluminum from Lowe's to build a mounting plate. Moved up the propane tanks 3 inches to allow for the box.  I can share pics once I am complete.  The single 200ah lithium is actually lighter than my current deep cycle battery but it is very costly.

[Merlin]

Go on amazon or etrailer and look up Noco or Camco battery boxes.  They have all sizes.  I am preparing my tongue to mount a 4d sized 200ah lithium battery today.  Bought a small sheet of aluminum from Lowe's to build a mounting plate. Moved up the propane tanks 3 inches to allow for the box.  I can share pics once I am complete.  The single 200ah lithium is actually lighter than my current deep cycle battery but it is very costly.

That's quite the battery! You'll have the equivalent of 4 group 31 100Ah lead acid batteries. By all means post the photos after you install it. Are you charging it with the on-board converter, solar, or some lithium-specific set-up.

[Nealcrichard@gmail.com]

I have the tongue ready and mounting plate in place.  Once the battery box arrives I'll take more photos.  I'm going with solar as well,  planning on spending some time off the grid.  I  moved the propane tanks forward and had to add a 6" nipple below the selector switch because the hose wasn't long enough.  I had to rearrange the front leg to the generator stand, and install a plate with the dimensions of the battery box.  I also checked the height to make sure I have enough room to remove the lid when needed.

NOCO HM408 Group 4D Commercial-Grade Battery Box, Black, Size: Pack of 1 https://www.amazon.com/dp/B002WCUR0M/ref=cm_sw_r_cp_api_glc_i_Pym8FbBNKH2D3

12V 200Ah Lithium Battery Deep Cycle Battery LiFePO4 12 Volt 2560 Watts Hours Lithium Battery Pack Rechargeable Li-ion Battery 200Ah Deep Cycle | 10 Years Lifetime 7000 Cycles with BMS Protection https://www.amazon.com/dp/B08JSMCTL1/ref=cm_sw_r_cp_api_glc_i_Hzm8FbDXB5C1D