Batteries and plastic boxes

I'm kinda confused here.i was always taught with batteries before that you needed ventilation. But now that I got a boat I noticed all my batteries are in plastic boxes with no ventilation holes. So I'm kind of confused since my charger is constantly going on the dock, that means better is a constantly being charged. And that means they have to be off gasing. So how can it be in a box then and be safe. Shouldn't the boxes have a holes drilled in them. I understand trying to keep the acid contained if something happens. That's it doesn't do anything about the gas. Can anybody kind of explain this to me I'd certainly appreciate it.
Thanks, Jack B.

Yes, usually there are holes in the top of a battery box to let the gases out. If there no holes you could drill a few.

Is it sealed where the wires are?

Jack Balkenende said:

all my batteries are in plastic boxes with no ventilation holes

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So each battery is in it's own plastic box with no holes? Are you describing maintenance free or AGM batteries?

No there's a little space around the wiring I didn't think that was really enough so yeah I think I'll take that suggestion and drill some holes

I have seven batteries one box says two six volts are together other box at two six volts wired together the other box has two six volts wired together and then I have a large box with a 12 volt in it for the engine

Liquid acid batteries

Thanks to those that answered to my post,as you can tell I am new to the larger boat big learning curve.you all have been very helpful on this forum I am so happy I found you all.
Learning every day, thanks,Jack B

Most of those plastic boxes are actually glass reinforced plastic, aka, fiberglass.

In the old trawlers, they were designed to hold a 8D lead/acid batteries and the wire slots provided sufficient ventilation.

But then, those are really heavy batteries. As people aged along with their boats, they started replacing each 8D with two to four (based on rating and size) lighter weight golf cart batteries. Then just regular batteries - ooops.

Well all these batteries in a single box needed more ventilation than a single battery and soon the plastic boxes held in the heat. Unfortunately, when batteries hit a certain temperature, they stop charging.

You could switch to AGMs next time around, just make sure your battery charger will switch to an AGM setting as well.

You could drill more holes or get rid of the lid entirely, just make sure that if you expose a positive terminal that it gets a little red hat to insulate it or the CG will ding you. And, make sure they are strapped in as well.

You could go back to the right sized 8D as well.

The boxes we had on our DeFever each held two 8D's and the Generator box held one 8D.

All lead acid batteries, even AGMs, require ventilation at the apex of any lids, so not just where wires enter if a gas pocket could form above this. Off the shelf battery box lids come with these vents built in, many boat builder made boxes do not, they should be added for ABYC compliance.

IMO, non-flooded batteries, i.e. AGMs and gels don't require a box and ABYC guidelines do not mandate full containment. Thus, non-flooded batteries could rest in trays or within cleated margins, although all must be secured against movement.

My three big AGMs are in fiberglass boxes, but the lids are more like covers. There is no seal at all and air flows freely around them (were there any airflow in my lazarette).

Batteries require ventilation for two purposes, one to allow hydrogen to escape, the other to allow heat to escape. Boxes hinder both, especially the first, lids do anyway. If the lids have holes at the apex, that's all that's needed. Ideally, batteries should be separated by at least 1/4" between cases to allow better heat dissipation.
More here https://stevedmarineconsulting.com/battery-installation/

Lying, Sitka.

Thanks Steve. Are boxes required for lead acid batteries? Mine are all mounted in trays but not enclosed in boxes. They came that way from the manufacturer and was not an issue at survey.

backinblue said:

Thanks Steve. Are boxes required for lead acid batteries? Mine are all mounted in trays but not enclosed in boxes. They came that way from the manufacturer and was not an issue at survey.

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ABYC Standards are a little ambiguous on this, they call for "containment" but don't define that, so technically a liquid-tight tray would suffice. I don't like boxes per se because they hinder inspections, and retain heat, and I question their value...except for flooded batteries, which, albeit rarely, can explode, I've seen it a few times and if it isn't in a box it's a bloody mess. Again, a liquid-tight tray meets the letter of the law, so you are OK in that respect.

Departing Sitka

While we’re on this subject, anyone aware if ABYC has anything to say about how high batteries are from the floor of the engine room?
My battery tray in the back of the engine room rotted out. My boat yard relocated them to the floor on top of fiberglass rails which put them about 2-3” above the ER floor.

All 3 8Ds are secured and in battery boxes with lids.

I don’t seem a problem with that as long as the support is substantial enough for the weight of those monsters.

Yea, those 8Ds are monsters

Caused me my only extended episode of low back pain.
Day it happened I tried to hide it from my wife so I wouldn’t take a scolding on top of hurting. But had to sleep on the floor for 5 days so there was no hiding it.

Now bought something I think is called a Cabinitizer that is normally used to raise and install cabinets.

In my application, it can be taken to the boat, assembled in the engine room, and used to lower the batteries down with a crank.

I went that route instead of re-rigging the cables to accommodate golf cart batteries. That’s still my backup plan but this seems to work.

I can send a pic of this back/scolding saver if anyone interested.

QUOTE:I can send a pic of this back/scolding saver if anyone interested.END QUOTE:

The lift would be of interest.

I rigged a 4 block tackle system to lift my 5 x 8D in and out of the trays.
I screwed a H.D. screw hook, 1/4" into the wood stringers overhead with a couple of pieces of 1/4 thick aluminum plate in the two areas where I needed to use the hook with a machine thread and nuts to hold in place.
I use 3/16 short 'S' hooks for the final lifting point between the blocks and the rope handles. After retying the handle ropes for less sag.

It's not perfect and has undergone a couple of revamps but it works and means I can install/remove the batteries from the trays myself.

For the in/out of the eng. compartment and boat and to and from the truck I hired a couple of moving guys 2 times now who were great.

My floor boards allow me to slide the batteries around once into the eng. compartment and with the tackle I can finish the install without strain.

ORIF said:

Yea, those 8Ds are monsters

Caused me my only extended episode of low back pain.
Day it happened I tried to hide it from my wife so I wouldn’t take a scolding on top of hurting. But had to sleep on the floor for 5 days so there was no hiding it.

Now bought something I think is called a Cabinitizer that is normally used to raise and install cabinets.

In my application, it can be taken to the boat, assembled in the engine room, and used to lower the batteries down with a crank.

I went that route instead of re-rigging the cables to accommodate golf cart batteries. That’s still my backup plan but this seems to work.

I can send a pic of this back/scolding saver if anyone interested.

Click to expand...

Sounds interesting. My solution is to hire someone much younger and stronger. Also works well as a back saver. Even lightens your wallet!

Yeah, I’ve gone the hire the young buck route too.
Usually that’s my PA who I give a case of fancy beer to but I worry about his back too.

I can use this lift device for getting the batteries in and out of the truck. Load them on a dolly and wheel them down to the dock.

Then can use the lift to get them up to the gunnel.
Then gunnel to the salon sole. That’s the most at risk step of the process.

Then move the lift to the engine room and slide the 8D beast onto the lift and lower it down.

If I had to, I could take the lift in the truck to the purchase site but they seem to be ok with loading for me. I just don’t like to watch.

Main limitation of this would be the width of the base of the contraption as to whether you have room for it in your engine room. I had to take a little bit of a leap of faith that it would fit based on the product specs. I did conceptualized potential workarounds if it didn’t.

I’ll post a picture and a measurement of the base width when I get back home.

I’ve found it handy for other lifting tasks in my garage.

It’s pricey but so is my back…

Cabinetizer 76 Lift https://a.co/d/a3dWmLB

and sorry. Still haven't been able to figure out how to flip images around on this site