Battery Box Needed, underground, watertight

RichNJKubota · Aug 7, 2004

I'm putting up a few solar electric panels and an inverter outside. The inverter will have 8 car sized deep discharge batteries connected.
The batteries need to be placed in a watertight box in the ground. The top will be flush with the surface.
Does anyone know of a commercially available box with lid?
Perhaps something that a utility would use?

Thanks,
Rich

MikeIA · Aug 7, 2004

It's not underground, but I did run across this in one of my catalogs:

http://www.poweruptech.com/alphaod_ups.html

Darren · Aug 7, 2004

I wouldn't put the opening of the chamber flush with the ground unless there's a seal on the hatch that can withstand hydrostatic pressure. You'll also need a way of ventilating the chamber using explosion proof equipment before entering the chamber for battery maintenance.

For a chamber search the internet using keywords like shelter + buried + tornado.

Lazy · Aug 7, 2004

Hi
you might find something at this web page that would meet your needs.

Charlie

fractal · Aug 8, 2004

Your deep cycle lead acid batteries are most likely wet cells. They gas hydrogen. They need good ventilation and regular maintence.

I would be reluctant to put them in a "box below ground".

RichNJKubota · Aug 8, 2004

I should have mentioned in my first post that these are selaed lead acid batteries and do not require ventilation unless code requires it.
http://www.concordebattery.com/products/psb_eleclspeifications.cfm

Thanks,
Rich

tracdoc · Aug 8, 2004

Hi Rich,

Out of my own interest in these batteries, I looked at the website you posted. Fractal was correct. These are indeed lead-acid batteries, and all such batteries off-gas hydrogen gas during recharging. Still curious, I looked at the mfr's "MSDS" (a spot to click on their homepage). They state lead-acid, and list the hazards of lead and sulfuric acid, but no mention of hydrogen gas (!), though they certainly should have that. On reading down to near the very bottom under "Other Precautions" they finally state that ( battery may release hydrogen gas...do not store in an airtight container. )

I don't know what they mean by "valve regulated" in their ad. Does that have to do with hydrogen valve, or something else?

Bottom line, IMHO for your personal safety, I would recommend you reconsider burying these in an air- watertight container system.

Best...

RichNJKubota · Aug 8, 2004

From what I understand the way these batteries work is that they recombine the hydrogen and oxygen gasses back to water instead of venting them as flooded lead/acid batteries do. The only time they will vent is when the pressure valve in the battery opens in case the batteries are severly overcharged.
And yes, you are correct that the box needs to be vented to the outside but I'd like to start with an airtight box and put my own hole it it.
The box will be in the ground and under the PV panels so not alot of rain will be falling on it. I'm more concerned with moisture from the ground infiltrating a poorly made box and then condensing in the box making a mess of the inside.
I'm also considering a hole in the bottom to let water out that will make it's way in.
If it looks like this will not work then the batteries will have to be placed in the house and that has it's own safety issues along with a very expensive wire to get the power at 48V/100Amps (and 250ft) from the PV panels to the inverter/batteries in the basement.
Everyone involved in this project but me is sold on the battery box solution - from the electrician to the electrical distributor, designer, inverter manufacturer and battery manufacturer.
I'm still sitting on the fence and waiting to see if the box will work without problems in the future.
The distributor has suggested using a "hand hole" or "ground vault" fiberglass box as used by utility companies.
Thanks for your replies and keep them coming,
Rich

Darren · Aug 8, 2004

If you purchase a watertight container, I wouldn't knock a hole in the bottom. Depending on the water table height you could end up allowing water to enter from below. Since you are in NJ, I suspect the building inspector will require a ventilation system. I'm sure you know you live in one of the PITA states for codes. Unless you have a connection with the local building inspectors, you may be in for an education.

Good luck!

SPIKER · Aug 8, 2004

If you can't FIND something then maybe contact some LOCAL MFG for steel fab shops, they can probably BUILD you soemthing from Stainless Steel pretty cheap if they ahve it oN-HAND/STOCK already...

then you get one built to you're needs and make it custom...

add a few racing stripes lol.

as for OFF THE SHELF it is harad to say, you need SIZES to give us, and for them too.

Mark M /forums/images/graemlins/smile.gif

Mark M