Battery acid fumes, ideas?

Craig LaForce · Post by **Craig LaForce** » Sun Oct 22, 2006 4:02 pm

I am finally convinced that the fumes from the batteries is what is corroding all of the metal stuff (silverware, cooking tongs etc). in my galley drawers. I suppose the acid fumes are heavier than air and just hang under the galley and in the bilge.

Also my port fuel locker is now empty, thanks to the suggestion of using 2 of the neptune tanks in one locker.

Idea #1
install a bilge blower to suck the fumes out of the battery area, and vent it with a 3 inch hose to the port fuel locker somehow. Might also be a good idea anyway to get rid of bilge air occasionally. I would run the blower when the charger is on.

Idea #2
Relocate the 2 batteries to the port fuel locker and let them vent all they want, outside. But would need to make sure they are secure up there, and it will not help the boat stability any.

Idea #3
not the answer for me, cause I am a cheapskate. Buy some newfangled gel cell batteries.

ANy other ideas?

Night Sailor · Post by **Night Sailor** » Sun Oct 22, 2006 9:04 pm

RV dealers or parts stores sell plastic battery boxes that have built in 1.5 inch vents in the top designed to hold 1.5 inch hoses to carry fumes outside. The shorter the hose run the better. If I recall correctly, about $15 each.

Don't move the batteries to the stern fuel bin as that puts two much weigh aft and on one side, raises the weight above the designed center of gravity, and subjects them to wider temperature extremes if the boat is not trailered but stored wet.

When the batteries expire, get the sealed batteries, like Optima, they are worth their extra cost in space, weight and hassle saving. Mount them under your bed if you wish, for they regenerate instead of outgassing.

Post by **kmclemore** » Sun Oct 22, 2006 9:12 pm

Don't know what year or type of boat you have, Craig, but I have a 1998 26X and I moved my batteries to the front, under the v-berth's port hatch cover. I have two in there, side-by-side, on a plexiglass platform. On the opposite side I have my water cannisters, so the two kinda balance each other out (at least when the water is full!

)

(BTW, this was just when I got the boat - the wiring has been much improved and now there's a solar charge controller and a Xantrex Link 20 in that area, too.)

James V · Post by **James V** » Sun Oct 22, 2006 9:21 pm

Hummmmmm, Do you have the plastic boxes that you can put the batteries in?

You may want to get these as when the boat heals the acid collects in them and if you put baking soda inside it will help handle the acid.

Vents in the lockers are a good idea. I have been wanting to put a 2 inch hole with somesort of premade cover in every locker. I should not need a fan with enough of them.

Post by **Hamin' X** » Sun Oct 22, 2006 9:45 pm

You need to find out why your batteries are out gassing so much. This is not normal. There is only one reason for out gassing and that is over charging. The two main causes for overcharging are: Faulty charging system, or bad, or weak cell in one of the batteries. If you have a weak cell in one of the batteries and it is connected to the other battery, both batteries will be over charged. You will need to check the specific gravity of all the cells, in both batteries.

Rich

mike uk · Post by **mike uk** » Mon Oct 23, 2006 1:03 am

Battery gasses are in fact lighter than air so a well cosidered location with good ventilation is all that should be needed - blowers should be unnecessary. As mentioned above, batteries shouldn't gas very much anyway unless something isn't quite right.

Maybe the corrosion is being caused by a combination of damp and cheapo stainless steel - consider buying some nice quality Sheffield stainless cutlery

Mike

Craig LaForce · Post by **Craig LaForce** » Mon Oct 23, 2006 3:28 am

THanks for the replies.

WHile I know that H2 should be the main gas produced and is light, it seems like the acid might in some form be leaving the batts as a vapor?

I have a '97 26X . replaced both batts last year and have only charged them a couple of times this year in an effort to minimize any gassing .
THey are the normal marine deep cycle 12 V batts acid-plate type.
I have a 2/8/12 amp smart charger from Schauer. It is a compact charger and it hangs on a rope tied to the galley pole just above the batt compartment.

THe cutlery was indeed cheap stuff that I bought for the boat so maybe that was the main culprit, along with general humidity. I also had a few screwdrivers and some pliers in one of the drawers and they rusted like crazy.

I did buy a couple of battery boxes when I first bought the boat but never used them. The lids just sort of flop on them, and no outlet pipe connection or anything. Maybe I should look for the better type that you mention that can use a little vent hose.

I used to think the corrosion was from salt air, but the boat has been at a fresh water lake for the last 2 seasons, and no difference in corrosion.

The thing that makes me think it is the batts, is that tools don't corrode elsewhere in the boat so much, just under the galley.

I have a little hydrometer and will check all the cells next time, along with the water levels.

If some acid spills, I wonder if it can react with the wood I have them sitting on and create some corrosive gas? I have one batt in the original spot and the other one under where the cooler used to be (aft dinette seat .

I agree that the aft fuel locker is not a good idea for the reasons you stated, so will try the bilge blower idea first and maybe move to a different more expensive battery type next change out. The bilge blower will also remove any heavier than air fuel gases that might otherwise collect over time from misc stray sources.

THanks

Robert · Post by **Robert** » Mon Oct 23, 2006 4:47 am

AGM batteries do not vent to the atmosphere unless they pop their pressure relief. AGMs can even be mounted on their side. UPS will ship AGM batteries because they are not an acid leak hazard. AGM batteries can last the whole off season without a trickle charge and still get your boat started next season.
..
I swappd out my starting battery to AGM first month I owned my boat to avoid the bucket-of-acid in the closed bilge mess. I started off with AGM for the house battery.
..
Whatever battery you choose, protect your investment by keeping them properly charged.
..

http://www.dcbattery.com/agmtech.html
..

http://www.optimabatteries.com/publish/ ... arine.html

Frank C · Post by **Frank C** » Mon Oct 23, 2006 7:18 am

James V wrote:Hummmmmm, Do you have the plastic boxes that you can put the batteries in?

You may want to get these as when the boat heals the acid collects in them and if you put baking soda inside it will help handle the acid. ...

As James suggests, I installed a plastic battery box (Wally-mart, ~$10 ea) under each battery to catch any overflow.

Little-known fact:
the properly installed battery box and cover will trap a bubble of air over the battery. It's no guarantee, but in some circumstances this could permit a battery to continue powering emergency equipment ( i.e. the VHF radio) even after the battery compartment was completely submerged.

No, I didn't install the battery box covers ... either ... too much effort.

R Rae · Post by **R Rae** » Mon Oct 23, 2006 8:25 am

When you visit Wally-Mart per Franks suggestion, why not replace all of your silverware, tongs etc. with plastic ware. And if you should require the high end stuff, then pay a visit to your local party supply store!

Night Sailor · Post by **Night Sailor** » Mon Oct 23, 2006 2:23 pm

If you decide to go ahead with a bilge blower, consider that normal marine blowers have a huge energy drain while in use. Perhaps a passive collection device such as a clamshell vent could be used to funnel air into the compartment or suck it out.

Craig LaForce · Post by **Craig LaForce** » Mon Oct 23, 2006 5:34 pm

I would just use the bilge blower while the batts are being charged and of course I have shore power then.

I bought a 3 inch blower for 20 bucks at Acadamy sports, and hose, a vent fitting and yet another fuse/switch panel at West marine. 3 switches, plus a 12V lighter plug and a volt meter test. My cheap solution is already about the cost of an AGM I would guess.

I guess those are the batts I will eventually get. Do you have to hit a different button on the smart charger for them or get a special charger?

Divecoz · Post by **Divecoz** » Mon Oct 23, 2006 6:37 pm

I am no chemist that's for sure . But isn't there some kind of litmus test that could be performed to show the presence of acid ? Then you would know for sure.

Post by **Hamin' X** » Mon Oct 23, 2006 9:53 pm

Your "Smart Charger" may be the problem. Check the individual cells, as I advised. Then check the charging voltage at start, mid charge, finish charge and float charge, to make sure that the charger is not over charging. That is of course, if all of the cells are good. Also check and clean all connections, as bad ones can produce bad signals to the charging system and result in over charge.

Rich

Craig LaForce · Post by **Craig LaForce** » Tue Oct 24, 2006 2:50 am

Litmus paper would work I guess. You can buy it to check for seveal PH color change points I think.

Not sure where you buy it though other than the internet somewhere.

The smart charger is probably not overcharging. I have been very sparing with plugging it in, and even then, it turns off pretty quicly and says it is fully charged.

But the charge rate is a little faster than my old ferro resonant charger was. Maybe this increases gassing even if not overcharging.

MacGregorSailors.com

MacGregorSailors.com

Battery acid fumes, ideas?

Battery acid fumes, ideas?

Avoid the whole battery vapor issue go AGM

bilge blower