Battery locker ventilation?

[beamishken]

I recently took a sailing club rib out & on trying to start it just clicked
The battery lead was lose & had arked out
The locker smelled strongly of hydrogen sulfide which I know is an explosion risk, I suspect the battery had a dead cell causing it to gas off.

What's the normal set up with battery compartment's in consoles as I'd expect to see ventilation to prevent the build up of gases

This is a production boat that I assume was professionally rigged
I'd be interested to know what the correct set up is
Cheers
Ken

[James3402]

RCD rules says if it's a newer design can't remember the date it should be a vented space..

[beamishken]

I thought ventilation was pretty essential but was starting to doubt my own thoughts when I saw this boat
Cheers for confirming what I already thought

[ShinyShoe]

Not required for certain closed batteries. If that was trivially specs but replaced by an open type my club...?

Or could there have been vents which have been obstructed...

[chris123]

All lead acid batteries will gas under fault conditions (ie dead cell / faulty charge regulator). Sealed lead acid batteries are somewhat misnamed - yes, under normal use they are effectively sealed, but under fault conditions they will produce gas and have valves to release the gas.

Cheers

Chris

[beamishken]

Shinyshoe looks like your autocorrect altered your post .
I assume your saying no ventilation is required for sealed type batteries if origionaly fitted & battery could have been subsequently changed by the club which makes sense

The locker is only just big enough for the battery with a hinged sealed lid on the side of the console below the helm seat the fact it's such a small space makes it more of a risk combined with a battery which was clearly gassing off & a loose lead that could have sparked at any time, the consequences could have been dangerous

[ShinyShoe]

Yeah sorry trivially = originally and my club = by club.

I haven't checked the wording of the rules but my understanding was they only need a vented space if its an open type battery... If I was a boat designer I might decide vent = water ingress = failure. So spec it to run a sealed battery. Plenty of consoles are used to store fuel tanks and I'd think vapour from them with sparks is more common than HS. So then club replaces battery at some point and fits an open type unaware of issue...

Or if the rigging is not done by the builder but by dealer do they need to comply with RCD? Or club rigged it to save £. Builder may have intended a separate battery box...

But also seen consoles that could be argued a bilge type drain is the ventilation but then a rag, first aid kit, flag, rope etc all end up in the bilge reducing the effectiveness...

[Hightower]

It's wise to ventilate a battery/electrical compartment. be careful how you do though. You don't want to be drilling holes below the water swamp line WSL (Just made this up). In other words the water level reached if you RIB got swamped with water by a wave.

The other advantage to venting a console is to stop condensation building up.

[Searider]

Very few ribs I look at have adequate battery compartment ventilation as built.
For a coded boat if additional ventilation is required I ask for a vent as high as possible in the space. This can be shielded to prevent water ingress.

Battery gas, hydrogen, is lighter than air so needs high level ventilation.

Petrol vapour is heavier than air so needs low level ventilation.

You shouldn't have electrical equipment in the same compartment as the fuel system although many do.

[beamishken]

Maybe it's not a problem most people would spot but I remember when I was 16 putting a battery on charge in a landrover with the battery box between the seats .I left the battery box lid proped up between the seats & another mechanic reached in knocked over the lid onto the charger leads which shorted & blew the top off the battery
He chased me allover the yard threatening to kill me when he caught me
Thankfully I could run faster then

[Nightfisher]

Without seeing it, I'd suggest starting from the main 12v Batt..looking at every connection for corrosion or arching (greyish-greyish black). Cripes can help newbies on low-amperage stuff such as radios, LED lighting. But after that properly soldered and sealed and above deck fusing will allow for cool runnings most of the time. When dealing in salt water conditions, always expect a disappointment sooner or later IF NOT CONTINUALLY checked/Maintained. If you see a crimp--would suggest inspecting for the above before continuing down the line. Lastly, above-board switch fusing will certainly corrode sooner or later.

[Nightfisher]

Chris' right. Over-due ventilation always. Don't go by specs.