Adding battery box in steps?

[pago cruiser]

Looking at adding (2) batteries to the current (2) "in-floor" batteries in a Winnebago Aspect 26A. The steps are not being used for this - yet many RV's have their coach batteries in this location. It looks like they would fit.

Have spent more time than I would like to admit looking for a pre-made solution; like a 12G metal powder coated box with a flange that would just "drop in", with a hinged top to then install your flooring upon.

Anybody done something similar, or seen something "off the shelf"?

[HarryStone]

If you use lead acid batteries, make sure the 'box' is vented.

[pago cruiser]

Thanks for the response.

Actually, these will be something along the lines of the Battle Born 100AH 12V LiFePO4 lithiums. Going to this much effort to fab/build a new battery box, may as well get the most bang for the buck.

(4) of the BB LI's (124#) are only 20% more weight than than the (2) lead-acid Group 27's (100#). So while ventilation will not be as critical as lead-acid or AGM, I am still thinking of some means for ventilation - maybe holes in the battery box sides?

Coming from a cruising sailboat when we were dragging around a pair of 8D's (each at 150# and the size of a microwave oven!) battery tech has come a long way.

That said... as I think about it, I have not seen any ventilation in any of the photos of batteries-in-the-steps in Class B/C RVs. Just seems like batteries jammed in tight with a hinged lid.

Heck - maybe they count on the hinged lid acting as a pressure relief vent...