AGM Battery inside where we sleep?

[Bezoar]

What are you thoughts of locating a maintenance free AGM battery inside my trailer? I think it might be too heavy to put on the tongue (I went with a 200 ampHr @ 126 lbs)

I couldn't justify the Lithium budget-wise right now, with the cost of constructing the trailer. (are they injecting gold into the wood products these days?) We took a similar tack with our house building - spend the money on the "bones" and you can upgrade the other stuff later. (20 years later and we haven't upgraded the vinyl floor or laminate counter tops, they still look good!)

Anyway - If I put the battery in a cabinet inside, am I going to kill us? Does it need to be vented to the outside? Does sealed mean sealed?

[TimC]

Should be OK. But, my first question is... is the cabin ventilated and will you run the ventilation continuously? A 12v case fan is a nice way to make sure you have some fresh air exchange while you are in the cabin. Among a few other benefits. So, if you are putting in a big air pusher like a fantastic fan consider a little case fan as well to move a little bit of air all the time, almost silently and unnoticeably. I have two 33cfm fans in my cabin and they change the air about once every four or five minutes. And burn very little power to boot!

Tim

[Socal Tom]

Put it in a battery box that is vented to the outside.

[Tom&Shelly]

Put it in a battery box that is vented to the outside.

+1. AGM batteries don't vent unless something goes wrong with them. (Specifically, an overcharge, but there are things that can go wrong internally in the battery that can cause that to happen.)

Tom

[working on it]

* I've slept many nights (probably 20 or more over many years) in the back of my '09 Chevy HHR Panel, when I got iced-in at work (DFW usually gets ice in winter, not snow). A 120+ mile round-trip to home and back, plus 12-16 hour workdays, made very little turn around time, so driving home on ice was not an option. I first used an aluminum topper on a '75 C-10 as a refuge, but the HHR Panel was bought with such a purpose in mind, to replace it.

* The HHR Panel has a battery in the rear, under the floor, where my head rested. Though it wasn't an AGM, but a normal lead-acid wet cell battery, I never detected any hydrogen sulfide odor rising up (and I borrowed a detector from building maintenance to double check). Since the battery wasn't being used, or charged, at the time, it wouldn't produce much hydrogen sulfide anyway. I wouldn't hesitate to have an AGM underfloor, as there's less of a hazard using them in close proximity.

[TimC]

Whether your battery is inside or outside the cabin another consideration is how your battery will be charged. If using a charger use a modern "smart" charger. Old technology chargers have a good chance of overcharging and causing damage to any battery if left connected too long and should never be used with an AGM battery.

If charging via a solar charge controller it will monitor battery status and go into trickle mode when full. Quality solar charge controllers can be left wired to your battery with little risk of overcharging.

Tim

[featherliteCT1]

I had several different Volkswagen Beetles in the 1960’s and 1970’s. All had the lead acid battery installed OEM inside the vehicle under the rear seat. I never smelled any sulfides. I suspect that the battery charge system was not very “smart”. I wonder how safe or unsafe that was.

[kludge]

"But the “valve-regulated” part of the battery description refers to a vent. In the case of AGM, it’s a pressure-relief valve, usually opening between 1 and 2 psig. Charging too quickly produces hydrogen at a rate faster than it can be absorbed into the glass mat. If this occurs long enough, pressure will build inside the battery, and could force the valve to open."

https://rvnerds.com/2017/11/01/electric ... d-venting/

[tony.latham]

If it were me, I'd install the AGM battery in the cabin and make sure it was being properly charged. This is easy to do with a Noco or other charger with an AGM setting or the same with a solar controller.

It won't emit hydrogen if it's being properly charged.

But that's just me.

Tony

[featherliteCT1]

To clarify, my understanding is that during normal charging, a lead acid battery will emit hydrogen gas, which is harmless to health, and only causes a problem (i.e., a fire hazard) if allowed to accumulate in a closed off area with no means of dissipation (e.g., in a completely sealed off tight space).

However, if the battery is improperly overcharged, the battery will dissipate hydrogen-sulfide gas, which is harmful to health, even in low concentrations.

I assume AGM is the same chemical reaction except that with an AGM, the hydrogen gas gets reabsorbed back into the mat.

So, I agree with Tony.

[pchast]

Its so easy to vent a compartment.
It shouldn't really even be a question, in my mind.

[Tom&Shelly]

If it were me, I'd install the AGM battery in the cabin and make sure it was being properly charged. This is easy to do with a Noco or other charger with an AGM setting or the same with a solar controller.

It won't emit hydrogen if it's being properly charged.

But that's just me.

Tony

I dunno. Is it possible that weak cells inside the battery could "fool" a charger, causing the stronger cells to be over charged? I've had that happen with an older lead-acid battery, where one cell went bad, probably because I didn't maintain it correctly. Basically it was a 10.7 volt battery at that point, but the charger (old fashioned dumb type, just designed to put about a half rectified 13 v on the battery) wouldn't know it; neither would a smart(er) charger or solar controller.

I don't know if cells in an AGM battery go bad together, or individually, as the battery ages. I wouldn't bet on them going together.

I'm with the "easy enough to vent" crowd.

Tom

[tony.latham]

I'm with the "easy enough to vent" crowd.

Okay. I'll sign the petition.

Tony

[Bezoar]

Thank you all for your responses. While the idea of another hole in the wall for a vent as potential water entry point isn't great, it beats explosive and or poisonous gas accumulation!

[tony.latham]

While the idea of another hole in the wall for a vent...

Yeah... but you might consider a marine vent.

https://www.westmarine.com/buy/seafit--stainless-steel-clamshell-vents--P012_363_001_507?recordNum=7

There's a lot of them out there.

Tony