Waterproofing Battery Terminals?

[arrabil]

In all the waterproofing things I've read I have never seen anyone waterproof the battery terminals. I take it that means its completely unnecessary. But why? Does that also mean your batteries can be submerged without problem since they're sealed?

 

[warhawk]

I wouldn't submerge a battery, it would be basically the as shorting the polls with a wrench.

If you're relocating your batteries try to put them some where that they will stay mostly dry. If you're really worried about it I'd put it in a marine battery box and/or some rubber terminal insulators. That's all our boats have at work.

These are the boxes I'm talking about.

These are the terminal insulators I was talking about. You can pick this stuff up at a local marine dealer or a marina.

There is a compound that's sort of a paste that conducts electricity that you could coat you're terminals with that would help weather proof it even more, I can't remember the exact name of it off the top of my head, but the ETs at work use it to seal up antenna connections and such on the cabin tops on our boats.

 

[warhawk]

There is also this that the EMs use it's not exactly what I was talking about on my previous post, but it should work. It's liquid electrical tape.

Here's a link. http://www.sportys.com/acb/showdetl.cfm?&DID=10&Product_ID=104

 

[arrabil]

I wouldn't submerge a battery, it would be basically the as shorting the polls with a wrench.

Thats what I thought but I still don't see anyone doing it. Are you saying this guy has his sealed up?

 

[warhawk]

I would actually be surprised to find out that his battery is completely submerged all the way over the terminal. Even if his batter is front right or left, there isn't any water over the hood, so the water that's up to his head lights is the what is being pushed by his bumper and brush guard. That wave drops off so quickly I doubt his batter is submerged. There are all kinds of things between the front of a vehicle and a battery that would help keep most of the battery out of water.

 

[calypso93]

We used "Boeshield" and some type of spray on engine "preserver" on boat battery terms. I wouldn't recommend long term submersion, but an occasional wash over the tops didn't seem to hurt. The type of connectors are a larger concern. Water, and definitely moisture (thru temp changes) can sometimes find it's way into battery cable, thru a non-sealed cable/term junction. It's not noticeable until the wire corrodes inside the outer jacket. Some connectors are wide open to water infiltration, some look sealed. The only way to know is do it yourself, or buy premade cables with a pedigree.

 

[Will]

Fresh water (meaning, not salt water) has a vey high electrical resistance. I beleive if you had pure distilled water it would be non-conductive. You aren't going to short out a 12V battery in a pond or lake. It may conduct some, but nothing you would notice. Salt water, on the other hand, is a pretty good conductor. In fact, they use salt water as electrolyte in some very large batteries. But even then, Hummers have the batteries pretty low and I've seen them up to the windows doing landings without a problem.

None of that stuff pictured up there is waterproof. You can get a real waterproof battery box from an RV supply center. Many RVs have the battery inside under a seat. The lid is gasketed and held on with thumbscrews around the perimeter. There is a big hose on the top that leads to a vent on the exterior of the RV and another smaller hose for a bottom drain. Something like that could work, but you don't need it.

 

[arrabil]

Thanks Will.

but you don't need it.

This was the only part I was certain of before I asked my question. Just trying to learn...

 

[MAKG]

Distilled water is not an insulator, but you would never want to build a circuit out of it. Hard (but fresh) water is a weak conductor. Salt water conducts decently, but still nowhere near as well as a wrench.

You won't short out the battery by submerging it. You may cause some corrosion. A truly sealed box is a BAD IDEA because batteries outgas some. The RV stuff Will describes is vented. But it's wild overkill.

For submerging, MUCH bigger risks are the ignition secondaries (spark plug wires, coil(s), and distributor cap if equipped), and especially the air intake.

Water WILL conduct 30 kV very nicely over small gaps. As will air, thin sheets of paper, and so on.