Ventilation of Battery Compartment

[coopec43]

Originally Posted by boatpoker

Where do you think the acid and gas went from this AGM ?

It probably blew the battery box to bits!


https://forums.g503.com/viewtopic.php?t=196001


" I often get the argument that a box or tray is not needed with sealed batteries. ABYC uses the logic that at some point the sealed battery may be replaced with a wet cell, which is a valid argument" (Wayne Canning Lic Surveyor)



Not very convincing.........


Clive

[coopec43]

The subject of battery boxes was covered in The Hull Truth forum and apparently the ABYC does not require battery boxes. They do stipulate there must be a box or tray to contain acid spills.

(Google ABYC and battery boxes Hull truth for full thread)


ABYC and battery boxes

74lbSteve When in doubt go to the source. From ABYC E-10, Storage Batteries. There's more to the standard but this is the section that addresses the question asked.

10.7
INSTALLATION
NOTE:
When installing flooded batteries on a sailing vessel, consideration should be given so that the orientation of the battery minimizes the uncovering of battery plates while heeling.
10.7.1
Battery mounting materials and surfaces shall withstand electrolyte attack.
10.7.2
Provision shall be made to contain incidental leakage and spillage
of electrolyte.
NOTE: Consideration should be given to:
1.
the type of battery installed (e.g. liquid electrolyte or immobilized electrolyte).
2.
the boat in which the battery is installed (e.g. angles of heel for sailboats, and accelerations for powerboats).
10.7.3
Fasteners for the attachment of battery boxes or trays shall be isolated from areas intended to collect spilled electrolyte.
10.7.4
Batteries, as installed , shall be restrained to not move more than one inch (25mm) in any direction when a pulling force of twice the battery weight is applied through the center of gravity of the battery as follows:
10.7.4.1
vertically for a duration of one minute, and

10.7.4.2
horizontally and parallel to the boat's centerline, for a duration of one minute fore and one minute aft, and
10.7.4.3
horizontally and perpendicular to the boat's centerline for a duration of one minute to starboard and one minute to port.
10.7.5
Batteries shall not be installed directly above or below a fuel tank, fuel filter, or fitting in a fuel line without an intervening sole, floor, or deck.
NOTE: This does not prohibit a battery from being installed directly above or below an uninterrupted fuel line.
10.7.6
Batteries shall not be installed, without an intervening barrier, directly below electrical equipment susceptible to attack from corrosive gasses.
10.7.7
To prevent accidental contact of the ungrounded battery connection to ground, each battery shall be protected so that metallic objects cannot come into contact with the ungrounded battery terminal and uninsulated cell straps. This may be accomplished by me ans such as:
10.7.7.1
covering the ungrounded battery terminal with a boot or non -
conductive shield, or
10.7.7.2
installing the battery in a covered battery box, or
10.7.7.3
installing the battery in a compartment specially designed only for the battery(s).
NOTE:
When batteries have both a stud and post arrangement, protection should preclude contact with any part of the terminal

[coopec43]

Originally Posted by john61ct

Just for batt leakage from AGM, very little is required.

Def need a tray and of course to secure them.

> If the LPG gas stove was going to leak gas I would think it would end up in this bilge section.
Now **there** danger danger is real. Active ventilation called for, and/or strict compliance with an established well thought out inspection protocol like ABYC.

I'll make up some f/g trays and secure them under the batteries.

As far as the LPG is concerned I'll run the bilge blower for 4 minutes when boarding the yacht. There will be a gas alarm. The gas plumbing will be carried out by a certified tradesman. The gas will be turned off at the bottle when not in use. (The two bottles are in a self draining locker)

Thanks John.

[sailinglegend]

Originally Posted by boatpoker

Where do you think the acid and gas went from this AGM ?

You can shoot a bullet through an AGM and they still work - with no acid leakage.

[boatpoker]

Originally Posted by sailinglegend

You can shoot a bullet through an AGM and they still work - with no acid leakage.

You have documented proof ?

[coopec43]

Originally Posted by boatpoker

You have documented proof ?

https://www.youtube.com/watch?v=WA1Y51x0fpE

Clive

[boatpoker]

Originally Posted by coopec43

Clive

Hardly scientific. They were just lucky that there was no plate contact.

Give it a couple of hours for acid to leach out of the gel like the one in the photo I posted.

Also no indication in that video of where the gas went. .... it does have gas ... or did.

Those were my two points.

[IslandHopper]

Well i don't know about the not leaking question, although i don't think there was much left to leak after this hit lol

Pretty Impressive though....

https://www.youtube.com/watch?v=rVevcL4F-Xc

....is this a Gun thread now

[sailinglegend]

Originally Posted by IslandHopper

.....is this a Gun thread now

I think people need to take this seriously. The cracked AGM posted by boatpoker on #90 must have been severely misused and is not one of the very few AGM batteries that are designed for marine use, and that means they should be able to repeatedly fall of a 3 metre wave. Too many boat owners go for the cheaper Telecom or Solar "standby" AGMs that will fail on a boat.

The only reliable AGMs are Lifeline, Firefly, Northstar and Odyssey. I know from Lifeline that they have never had a battery leak or even explode that is why AGMs can be transported as non-hazardous cargo.

My first set of Lifelines lasted 14 years. When equalised at 15.5v they only started gassing after 6 hours, but so slowly you couldn't hear them, only by spreading water over the valve did they showed one very very small bubble which took about 4 seconds to fill and burst.

Not all AGMs are created equal.

Caveat Emptor - you cannot afford to buy cheap batteries.

[john61ct]

> The only reliable AGMs are Lifeline, Firefly, Northstar and Odyssey.

overstating a little, and specific to NA market

but yes

Rolls / Surrette must have good QA over their OEM supplier.

Trojan AGM haven't been "proven good" for long enough, likely their LFP will overtake.

Full River not bad. . .

[Julien de Tilly]

Originally Posted by cal40john

You are venting hydrogen, it will all be at the top of your box so no need for a bottom vent.

Thanks Cal.

So now my question is not wether battery compartment needs or not to be vented, but how am I supposed to vent it OUTSIDE the boat ? Due to the location of the settee under which the batteries are located, it makes no sense to me to install a thru-deck pipe in the middle of the boat... If I drill holes on the side of the settee with some kind of protective grid over it, would the natural ventilation of the cabin be sufficient to prevent harm to material and person (as some says that hydrogen is a very corrosive gaz) ?

[john61ct]

Yes to that last, IMO.

To the extent your batt box is sealed up restricting ventilation that concentrates the vapours which **can** make for noticeable odors.

Some individuals are more sensitive than others.

Some cabins are more sealed-up than others.

In which case going to AGM will likely be a simpler and more cost-effective than building ducting.

But note if you have an engine compartment already venting to outside, piggybacking off that should be do-able.