FLA Battery in Equipment Shed, or Separate Deck Boxes?

[BackwoodsEE]

I have a decision to make very soon: how big of a solar equipment shed to get. If I want to include the battery bank in it, then it will be 5' x 10'. If not, it will be half that size (5' x 5') and I'll need to put the batteries right next to the shed in two big plastic deck boxes or directly on a concrete slab (already there) with a removable cover over them.

The Morningstar 600V-TS-MPPT manual warns, "The controller may be mounted in an enclosure with sealed batteries, but never with vented/flooded batteries. Battery fumes from vented batteries will corrode and destroy the TriStar MPPT 600V circuits." So, that doesn't look good for having a single equipment shed for both batteries and charge controller, inverter, etc. If I built a wooden box around the batteries and vented the interior of that outside, would that keep enough of the fumes away from the equipment? Would I still need to worry about corrosion of the galvanized steel of the shed? Also, NEC 480.9 calls for a corrosion-resistant support for the batteries, and the shed has a steel floor. I don't know if a sheet of plywood would be considered "corrosion resistant" enough.

Those 130 gallon plastic deck boxes are too small to fit all the batteries I have in mind, so I'd need two of them. It gets awkward.

I'm leaning toward the idea of a big wooden box with no bottom that could be lifted off the batteries to remove them. (They are 6V Surrettes weighing in at around 300 lbs apiece: a tractor, front end loader, and forks situation.)

Thoughts?

[organic farmer]

I have a decision to make very soon: how big of a solar equipment shed to get. If I want to include the battery bank in it, then it will be 5' x 10'. If not, it will be half that size (5' x 5') and I'll need to put the batteries right next to the shed in two big plastic deck boxes or directly on a concrete slab (already there) with a removable cover over them.

In a location where river flooding does not happen.

Insulated to allow easy of heating through the winter, along with a heating system.

If the shed gets buried in snowbank then ventilation will be hampered.

Cooling?

[BackwoodsEE]

Excellent points. Here's how I think I'm addressing them.

In a location where river flooding does not happen.

Check, although snowmelt and heavy rains could leave a half inch of water on the slab. No way it would go anywhere near the tops of the plastic battery cases.

Insulated to allow easy of heating through the winter, along with a heating system.

I never plan to let these go below 50% SOC, and it never gets below -10 degrees F around here anymore. If I ever got worried about freezing electrolyte, I'd fire up the generator and get the batteries fully charged.

If the shed gets buried in snowbank then ventilation will be hampered.

There will be a chain-link fence maintaining a few inches of separation between the snow and the battery box.

Cooling?

Probably a temperature-activated fan in the box that will run when needed and also at night to take advantage of the air that always cools down here after dark, even on hot summer days. Lead has a low specific heat, around 0.1 J/(K*g), but all that mass still takes a while to heat up.

[SunEagle]

Just make sure you add the kWh that fan is going to consume to your daily total usage.

Cheapest cooling is having good air flow and natural convection which allows the heat to escape. Adding electrical cooling just increases your battery size.

[J.P.M.]

. Lead has a low specific heat, around 0.1 J/(K*g), but all that mass still takes a while to heat up.

In such situations, thermal mass in terms of heat energy units per volume is one common way it's done, say cal./(C.* m^3), or BTU/ F.*ft.^3).