What is this foam stuff on my battery terminal?

freebo86

TJ Enthusiast
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Noticed this foam looking stuff on the battery terminal for a while now. Went to connect the Jeep on the battery tender while it’s parked and it seems to almost be more than last time I checked. This is only on the positive terminal too, negative terminal is clean.
What gives? I cleaned this off once and it returned so what’s going on?

thanks!

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Your battery is slowly leaking acid. This is normal for older batteries. You may eventually need to replace this battery. Easiest way to clean it is a paste made from a mixture of baking soda and water, followed by rinsing with water.

If you start noticing starting issues, consider replacing the battery with a sealed AGM battery. Odyssey and NorthStar are good brands to look at. The Group 34 will fit with no issues. The Group 24 will fit if you have the wedge type hold down, and is 1" taller with a bit more capacity.

I wouldn't be too concerned about it now. Just know that your battery's days are numbered. A preemptive replacement may be a good idea, but isn't necessary at this point. Consider carrying jumper cables if you don't already.
 
So that’s what’s going on! Well thank you. The battery is probably going on 6-7 years. It’s a summer Jeep so the battery doesn’t see a hard demand for starting as it would in Winter.
I’ll keep this in mind and when time comes get a new battery!
 
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To expand on what @Steel City 06 has already stated, the post is supposed to be sealed where it penetrates the battery top. Yours is no longer sealed and allows the acid to creep up the post. Remove the battery cables and clean them with a battery post brush and baking soda mixed with water. Reassemble and coat the posts with petroleum jelly. Replace the battery when it finally fails.
 
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So that’s what’s going on! Well thank you. The battery is probably going on 6-7 years. It’s a summer Jeep so the battery doesn’t see a hard demand for starting as it would in Winter.
I’ll keep this in mind and when time comes get a new battery!
That is the only reason I recommend an AGM battery. No acid to spill or wind up where it doesn't belong.
 
If you get a substantial leakage or purging of acid out of the two square caps on the top, that acid will drain right out those two little notches along the back the battery. They are nicely aligned with all of those nice wire looms behind the battery. Get AGM or at least find a battery with a body design that doesn’t seem to be made to cause trouble in a TJ.
 
Do your best to not get that crap falling down off the battery. That is the reason you see all those rusted/rotted battery trays.
 
They don't yet have the AH capabilities/capacity needed by many Jeepers.
Well I do know that they are using them in a 24.8 ah applications starting lycoming 540's in airplanes. it may not run a winch but it should be good for a start/run battery would it not?
 
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Well I do know that they are using them in a 24.8 ah applications starting lycoming 540's in airplanes. it may not run a winch but it should be good for a start/run battery would it not?
Probably but are we ready for their costs yet? I found 50-100 AH 12v lithium ion batteries to be >$900. Yowsa. It costs more to produce amps at 12v than it does at 24v.

Not to mention aircraft owners are less likely to balk at the higher cost of lithium batteries.
 
Probably but are we ready for their costs yet? I found 50-100 AH 12v lithium ion batteries to be >$900. Yowsa. It costs more to produce amps at 12v than it does at 24v.

Not to mention aircraft owners are less likely to balk at the higher cost of lithium batteries.
Whats funny Jerry is that airplane owners will take there Gladiators in to the dealer to get a $200 oil change and when they take their airplane in for the same thing that costs about the same, the Airplane mechanic is fleecing them by putting in 12 quarts of oil at $7 per quart and a $30 filter, plus labor. They don't bat an eyelash when paying the dealer though.
 
So whats a good AGM battery? Did a quick search my local store (Canadian) wands $250 for one of these AGM type of batteries..
 
Weight is paramount to an aircraft. And every owner knows it's an expensive hobby.
 
Weight is paramount to an aircraft. And every owner knows it's an expensive hobby.
Just like buying boat fuel at the gas dock. Yeah it costs a whole bunch more than at the gas station but I don't see your happy ass hauling 20 5 gallon cans down there and pouring it in so pay up.
 
So whats a good AGM battery? Did a quick search my local store (Canadian) wands $250 for one of these AGM type of batteries..

I have a Odessey battery in my 06. Oreilys agm batteries in the kids jeeps.
 
Had some free time tonight and pulled the battery out. Broke up that acts around the terminal then vacuumed it up. Removed the battery terminals and will clean them up with baking soda and water. Will be shopping for a new AGM battery come spring when I pull the Jeep out of storage.

I am in Canada so the O'reilys is not an option here. We do have Costco/Canadian Tire/Napa/Carquest etc. Not sure how much of a performance of name brand I need as the Jeep is non winter driven so it doesn't see harsh conditions or hard starting requirements.