Reviving old batteries

I bought three brand new batteries for my boat (one marine cranking for the engine and two deep cycles for the 24v trolling motor). I then ended up moving and kinda moth-balling the boat for three years. The batteries were very low on water. I filled them with distilled water since that sometimes does the trick, but no dice. Multimeter shows open, 8A charger needle doesn't move (zero amps).

Are they likely sulfated? Best methods for un-sulfating them? Other ideas?

I also have an older battery that simply "wore out" that I would like to revive. Its probably shorted I would guess since it just slowly made less and less juice over time until it finally wouldn't take a charge at all. I tried testing for a short with the multimeter, but its still making 0.5v, so I can't really know what the resistance is since the voltage skews the numbers.

Can you guys maybe point me toward a reference for how to do this stuff? I found a couple [very remedial] youtube videos, but lost interest after 5 minutes of safety instruction and then "how to remove the battery from your car."

Color me interested also

I have a 130 amp booster that i put on really really dead batterys. Leave it there for 5 to 10 min and then charge normally. Works sometimes.

I've heard of people zapping them with 110 volts.

I wouldn't do it, but I've heard of it.

Try boiling them for a few days. I have had Ok results with some deep cycles doing that. You overcharge them about 40 minutes at a time until they are warm and starting to bubble. Then let them cool down and repeat. the idea is that the bubbling actually cleans off the plates to some extent. I learned that from a friend with a bumper boat business. He has a lot of batteries.

bearmtnmartin wrote: Try boiling them for a few days. I have had Ok results with some deep cycles doing that. You overcharge them about 40 minutes at a time until they are warm and starting to bubble. Then let them cool down and repeat. the idea is that the bubbling actually cleans off the plates to some extent. I learned that from a friend with a bumper boat business. He has a lot of batteries.

Do this, then pour the acid out, flush the crap out with distilled water, and put the acid back in being careful to let the junk settle to the bottom of the bottle first.

http://www.youtube.com/watch?v=Supe1a3LW2U

i used to buy re-cycled batterys guy would cut te outer case off boil'em and put in new case and ill with freash acid at 1/3 cst of new but he's long gone now.

epsom salt added to what you have works too.

44Dwarf wrote: epsom salt added to what you have works too.

I would guess the Mg Sulfate would eat the crusties, but then how do you effectively get rid of the MgSO?

How do I test for the proper electrolyte? I always thought thats what these things were for:

But they only test state of charge and help identify weak cells.

I've never used one of those doo dads, but I thought they were supposed to check your electrolyte level. We use digital hydrometers at work to check our lead acid batteries.

We've also been playing with charging VRLA batteries at a slightly higher voltage to desulfate the plates and bring some life back into batteries. It's been working at about a 50% success rate. I would imagine the same thing would work on a lead acid batteries though. If you can adjust the voltage on your charger bump it up a few volts for a few hours and see what happens.

curtis73 wrote:

44Dwarf wrote: epsom salt added to what you have works too.

I would guess the Mg Sulfate would eat the crusties, but then how do you effectively get rid of the MgSO? How do I test for the proper electrolyte? I always thought thats what these things were for: But they only test state of charge and help identify weak cells.

Mguar had a diatribe on how to renew dead batteries. Can anybody dig it up? I tried a while back, but my search skills be lacking.

You should try a "bettery desulfator" gadget on it like this one:

https://home.comcast.net/~ddenhardt201263/desulfator/desulf.htm

It sends high voltage pulses through the battery to break up the deposits that are acting as insulators.

I'm curious about this info. Wish I'd waited another day or two to get a new battery for the Kawasaki...

I never let my doodads anywhere near battery acid.

OT, but where's that thread on motorcycle batteries? I thought it was Z. Woof who was singing the praises of A123 dry cell batteries.

spitfirebill wrote: Mguar had a diatribe on how to renew dead batteries. Can anybody dig it up? I tried a while back, but my search skills be lacking.

Looks like mguar's only remaining traces are quotes and replies to him.

search you tube you find a bunch of vids

search you tube you find a bunch of vids

The OMNIANSWER!!!

FWIW I picked up this battery charger at Autozone the other day for 53 clams:
http://www.batterymart.com/p-schumacher-15-10-2-amp-charger.html?device=c&network=g&matchtype=&gclid=CNGMsqrkrLgCFSVgMgodbRIABA

It says it has an automatic desulphation mode.

I had a battery wear out on me last week. When I would pull it to charge it, my charger would indicate it already had a full charge. Voltmeter said 12+ volts too. Should have busted out the diagnostic device, didn't even think of it. Took it to shop and they said it was putting out 12V but only half the CCA it was rated for so that was why it wouldn't crank. Thought it was corrosion at the terminals so I cleaned the hell out of them, so thats a plus for a while.

Battery was six years old, so it was due. Never had this happen before. I am thinking about this while reading this thread. Interesting.

I tried the epsom salts in four of mine. I put a kinda random amount in them. I had a 1-lb box of salts and mixed it with a couple cups of water so it was mostly crystals with some saturated water.

All four batteries will now take a charge but not keep it for more than a couple days. I call it a marginal win. I at least have batteries that can be used for some purpose now and it cost me $3.

Put a load on the batteries and bring the charge to 0. Flush w/distilled water and service w/fresh acid. Then charge completely. It should take a charge, won't guarantee how long the charge will last but should at least get a couple cranks out of it. No guarantees if the plates inside are touching or too corroded.