Battery Box/Venting

[TheWire]

I’m getting close to installing a bank of 4 T-105 GC batteries for my cabin power system. I’m looking for some info on battery venting.

I have seen numerous homemade battery boxes using plywood with weather stripping to seal the door and a tube out the top for a vent. I’m assuming 2 purposes of a battery box are to contain and vent hydrogen generated while charging and to insulate the batteries.

I plan on locating the batteries in a small utility room in the cabin. I don’t think I need to insulate the batteries because I’ll want the cabin’s wood derived heat to warm up the batteries if using it for a winter weekend. Which brings me to venting. I’m assuming the main reason a battery vents is to get rid of hydrogen produced while charging. Instead of trying to create a sealed box, has anyone seen anything like a battery cap with a hose barb for a vent hose or have any thoughts on building a PVC manifold with a T that sits over each battery cap to vent the hydrogen?

Am I missing other reasons for a battery box/vent? Should I also be thinking about a pan below the batteries to catch acid from a cracked battery?

Thank you,

Jerry

[mike95490]

Am I missing other reasons for a battery box/vent? Should I also be thinking about a pan below the batteries to catch acid from a cracked battery?


I highly doubt hydrogen from a battery bank, in a homebuilt plywood box, could actually approach explosive levels, with out something being seriously wrong, like getting stuck in an EQ cycle. The best argument for battery boxes, is to contain the acid in case of a leak, or to contain the acid fumes/mist (green grunge deposits on tops of batteries) that emit as bubbling from charging increases as charge completes, or from an EQ cycle. You don't want to be breathing sulphuric acid mist, unless you are from Venus.

That's my opinion.

[icarus]

I currently have 4 t-105s. They are built on to a cart that rolls under my work bench in our shared work room. The cart allows them to be rolled out to work on them. I have a Phoenix fan with a voltage controlled switch that turns on at 12.8vdc. The whole system is lined with 2" styrofoam, sides top and from. Our batteries can be unattended for long times in the winter (-40) and the styrofoam keeps some of the self generated heat in. It also cuts down on the noise from the fan.

Works great, I just roll the cart out every month and check SG and water levels.

Tony

[crewzer]

Another reason for the battery box is to guard live connections, to protect people from the batteries, and to protect the batteries from people.

See NEC Articles 480 and 690, Section VIII (starting with 690.71) for code requirements for storage batteries. John Wiles also discusses batteries in the Batteries section (page 55) of his PV Systems and the NEC. Here's a link to the body (http://www.nmsu.edu/%7Etdi/pdf-resources/pdf%20version%20divided%20PV:NEC/DividedNECpt1.2opt.pdf) of his document.

HTH,
Jim / crewzer

[mike95490]

link sick:

Code corner
http://www.nmsu.edu/~tdi/Photovoltaics/Codes-Stds/codecorner.html

Body:
http://www.nmsu.edu/%7Etdi/pdf-resources/pdf%20version%20divided%20PV:NEC/DividedNECpt1.2opt.pdf