Old battery, new life?

[SkiprJohn]

Someone left an old battery on my vacant lot (nice of them?) and I brought it home. I added some water to the cells and put the charger on it. It is up to 12.75 now. One cell was nearly dry and I just added water. Can I get something else that would be better to add to try to salvage this thing or should I steal some from all the other cells and put it in the one cell that was a bit dry?
It is a large size starting battery and it'd be nice to have an extra around if I needed it.
What do you experts think?
JohnL

[Rick]

Once a cell has gone dry on a starting battery it will not recover. Although you may bring the battery back up to some indicated state of charge once a float voltage is removed you will observe a relatively fast self-discharge on that battery.

The only use it will have (reliably speaking) is if the battery does take a charge without exhibiting gassing on any cell when on a float charge and it demonstrates some ability to be used as convenient throw-away to keep around for non-critical starting applications. Otherwise don't waste your time...recycle the thing.

[senormechanico]

If you check the cells with a hydrometer, I'll bet you will find at least one dead cell.
Rick said it all.

Steve B.

[S/V Illusion]

congrats! you just adopted a heavy paper weight

[SkiprJohn]

Thanks guys. Like I said it was really nice of them to leave me a battery on my vacant lot. Hope it doesn't happen too many more times. I used to have a hydrometer around somewhere about 25 years ago. Think I'll get a new one.
Kind regards,
JohnL

[S/V Elusive]

Ya know ... it is funny that they did that. Most places require a 'core' turn in, or they charge an extra $20 or something. Could never understand why they would leave it someplace.

[S/V Illusion]

Originally Posted by S/V Elusive

Ya know ... it is funny that they did that. Most places require a 'core' turn in, or they charge an extra $20 or something. Could never understand why they would leave it someplace.

only if you are buying a new one. Stolen batteries, and the cars to which they are attached, don't come with a warranty.

[SkiprJohn]

This is a Wal Mart Starting Battery. They charge a $5 core fee when you buy a new one. Here it is hard to find anyone to take any kind of recyclable material because its an island. It is an 18 mile drive to the refuse dump. If they didn't buy a new battery to replace this one they probably just thought to toss it at my place.. Oh well. The price of living in paradise.
JohnL

[David M]

Just don't use it for any critical applications. Chances are about 99% that it is toast.

[GordMay]

The only possible use for a battery such as this, is as an output filtre, when (mis) using a battery charger as a power supply.

[Tom Spohn]

You could try one of these:

What is Nanopulser?

[jscott]

while it is likely dead.....

If you drain a battery it can be filled and work well....

If it was drained when fully charge, then battery acid can be added, and the battery will be like it was when drained. (That is the condition in which they ship new batteries, dry and ready).

When you added water you diluted remaining the battery acid (that was in an uncharged state).

So that cell will have a very low amphour rating now.

[SkiprJohn]

I think the battery will be a good conversation piece and might be good for testing 12v lights.
Does anyone know where to get battery acid to add? Should I be asking at an auto parts store?
JohnL

[Tnflakbait]

Could be wrong, but I think you should just add distilled water.

[SkiprJohn]

Aloha Tristan,
I don't worry about distilled. I catch our water on the roof and it goes into my 11,000 gallon tank. As long as the Volcano isn't blowing acid my way it is pretty pure.
Regards,
JohnL