... is now inside. :)Last summer our standard Lifeline lead acid and WFCO converter both died at the same time (while out on a long trip of course). On the positive side, I had been wanting an AGM battery for a while so I could mount it inside but it was a tough sell with the DW. Seizing the opportunity, I easily sold her on a "little" upgrade and ended up buying a new Trojan AGM and Progressive Dynamics converter/charger. A couple of years ago I built a new cabinet in the bedroom in a blank section of wall that had a large empty cavity behind it. I built it using doors and 1x2 trim from KZ so it would look factory built and I built it with the idea of putting the battery in there in the future. Mounted the AGM on a Sea-dog battery tray. We never dry camp but it's possible to fit up to 4 group 24 batteries in there. I ran #6 wire to the converter which is close by and an easy run under the shower stall. Now we have a space in the A-frame that I could perhaps use for a storage box.

Clever, but I think the DW would move the battery back outside and use the space for other storage. :)

bguy wrote:Is that a vented space? No, and I have thought about it but the chances of the battery overcharging and venting are remote with the new converter that is properly compatible with AGMs. I did buy a vent to put on the exterior wall if I end up having second thoughts. The location isn't tightly confined/sealed and not susceptible to overheating. One advantage of the AGMs is being totally sealed.

rbpru wrote:Clever, but I think the DW would move the battery back outside and use the space for other storage. :)Lol! Shhh, she doesn't know the space is there otherwise she'd have stuffed something in there by now... :B

Nice job on the mod:This is what I understand and have followed:From East Penn's AGM Technical Manual:"IMPORTANT: Do not install any type of battery in a completelysealed box or enclosure. In the event of overcharging,the potentially explosive gasses must be allowed toescape."So.....if you completely trust your converter then I guess you are good to go with the AGM'ms, but I know I would still install that vent that you have.

Our battery disappeared from the A-frame and ...

westend
Explorer
Jun 08, 2017
You need very little air transfer within the battery box to dissipate any hydrogen gas within. That would be using the model for FLA batteries. Since you are going to be using an AGM battery, you would only be engineering for an atypical "emergency" situation where the pressure vent opens on the battery due to overcharging/too much voltage.
I wouldn't hesitate to drill a small hole into the basement cavity to allow for air flow to dissipate hydrogen above. The hydrogen gas is so low in weight that it will readily seek the top most outlet and draw inwards from the bottom vent.
Alternatively, you could drill a 1/4" hole into the side of the battery box towards the lower edge of the box. That is all that is needed for the "make-up" air.
myredracer
Explorer II
Jun 08, 2017
I have an MTS Products sealed/vented battery box I removed from a previous TT that I put it in. Kept it for this TT if it looked like the right thing to do which it does. It has an inlet flange on the bottom. If I were to drill a hole into the underbelly cavity, could this be a problem? Don't know if there could ever be negative pressure under the floor that would draw gas into that space.

We don't use the furnace anymore because we never dry camp and have permanently installed electric heaters so air wouldn't normally get blown back outside via the battery box vent on the exterior. But air from the furnace will get outside anyway from all the leaks in and around perimeter of the coroplast.
pianotuna
Nomad III
Jun 03, 2017
Much more risk from hydrogen sulfide gas (rotten egg smell), which is an EXCELLENT poison, due to a catastrophic battery failure.

seaeagle2 wrote:
Lead acid batteries off gas Hydrogen, remember the Hindenberg ?
westend
Explorer
Jun 03, 2017
seaeagle2 wrote:
Lead acid batteries off gas Hydrogen, remember the Hindenberg ?
His AGM is a recombinant cell battery. As long as interior pressure doesn't reach the threshold of the safety release valves, any gases are recombined into the electrolyte paste. There are many AGM batteries in service in unvented areas. Typically, X-ray machines and telecom switching rooms are two of those.

Having said that and knowing the OP has tremendous DIY skills, and has air vent in hand, I'd suggest to install the vent. Depending on what style vent he has, the battery can be further enclosed to provide storage.

FWIW, when I vented my indoor battery box, I bought a really nice chrome plated vent with flapper from Best Converter. Don't think they sell that, anymore, but should be available elsewhere.
seaeagle2
Explorer
Jun 03, 2017
Lead acid batteries off gas Hydrogen, remember the Hindenberg ?
Lantley
Nomad
Jun 03, 2017
It needs venting. Any mechanical device can malfunction. What happens when you convertor overcharges the battery despite their claim it will not despite.
GrandpaKip
Explorer II
Jun 03, 2017
I would vent it because Mr. Murphy is always lurking about.
webwrangler
Explorer
Jun 03, 2017
downtheroad wrote:

Thx for the info. Does a "sealed box or enclosure" mean something that is just large enough to house a battery? There is a good sized volume of interconnected space around the shower and in through the bathroom vanity. The PD 4600 series converter upgrade will not overcharge a battery according to their info. which is one reason I wanted it.

Not only is that gas (should you get any off the batteries) explosive, it can make you dizzy and nauseous. Been there once in a truck I drove and I never want to feel like that again.
pianotuna
Nomad III
Jun 02, 2017
Add a vent to outside.
myredracer
Explorer II
Jun 02, 2017
myredracer wrote:
downtheroad wrote:
Nice job on the mod:

This is what I understand and have followed:

From East Penn's AGM Technical Manual:

"IMPORTANT: Do not install any type of battery in a completely
sealed box or enclosure. In the event of overcharging,
the potentially explosive gasses must be allowed to
escape."

So.....if you completely trust your converter then I guess you are good to go with the AGM'ms, but I know I would still install that vent that you have.

Thx for the info. Does a "sealed box or enclosure" mean something that is just large enough to house a battery? There is a good sized volume of interconnected space around the shower and in through the bathroom vanity. The PD 4600 series converter upgrade will not overcharge a battery according to their info. which is one reason I wanted it.