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OT, mostly looking for experience with lead acid battery desulfator/pulse charger

gbent

Diamond
Joined
Mar 14, 2005
Location
Kansas
I have seen hype and expensive boxes promising to recover a significant of dead/sulfated lead acid batteries. Does anyone have any direct knowledge of these devices or experience? Batteries are getting expensive, but not so expensive I am going to go the way of the utube reconditioners and dissemble to scrub the plates.
 
I have seen hype and expensive boxes promising to recover a significant of dead/sulfated lead acid batteries. Does anyone have any direct knowledge of these devices or experience? Batteries are getting expensive, but not so expensive I am going to go the way of the utube reconditioners and dissemble to scrub the plates.

IIRC Milacron posted on this subject a few years back.
 
I have seen hype and expensive boxes promising to recover a significant of dead/sulfated lead acid batteries. Does anyone have any direct knowledge of these devices or experience? Batteries are getting expensive, but not so expensive I am going to go the way of the utube reconditioners and dissemble to scrub the plates.
I use a constant current charger that is physically about a 16" cube and weighs perhaps 75 lbs, that has brought many electric pallet jack and electric forklift batteries back to life. Not a total panacea as the typical end result run time is about 40% of a new battery...but for my purposes that is good enough. Mine is "The Stablemate" by Energy Systems..but they seem to be out of business. It runs on 115 volts and will charge any voltage...12 to 48. Has a setable timer for 6, 12, 18 and 24 hour charge times.
 
I bought a new charger a couple years ago to replace a much older one that sank in a flood. The technology in this one is new to me as electronics have taken over functions.

So I had a battery that was in a parts car, no idea of history or state, but I hooked up the charger just to see how it responded - the battery that is. The charger displayed "SULF" and the instruction manual said it might do this for hours and hours as it tried to resuscitate the battery. Some day or two later it displayed 12 volts. I haven't tried to get it to do any work yet, but I was surprised that the charger thought it might actually do anything at all.
 
I bought a new charger a couple years ago to replace a much older one that sank in a flood. The technology in this one is new to me as electronics have taken over functions.

So I had a battery that was in a parts car, no idea of history or state, but I hooked up the charger just to see how it responded - the battery that is. The charger displayed "SULF" and the instruction manual said it might do this for hours and hours as it tried to resuscitate the battery. Some day or two later it displayed 12 volts. I haven't tried to get it to do any work yet, but I was surprised that the charger thought it might actually do anything at all.
I've had many conventional chargers refuse to even attempt a recharge on a highly sulfated battery...but my constant current charger has brought many industrial batteries back from the dead.
 
I have not had great success, just marginal success at reviving old batteries. For multi battery applications like diesel trucks you can replace all but 1 of the batteries with supercapacitors, cost is greater upfront, but they don't die as fast, not sure how long they will last either.
 
Never tried the pulse types, but I've never yet had a constant current type charger bring back a battery to any reasonable performance.

Generally, even if they did come back to nominal volts, when charged "for real", they shorted, or otherwise failed, dropping back to a lower voltage. And the couple that seemed to work OK had a fraction of the capacity they should have, possibly because the sulfate dropped off, possibly because much of the sulfate was not "reachable" by the current.

Supposedly the pulse type will convert sulfate that is not "reachable" so long as it has not actually fallen off. I don't know about that, as I've not tried one.

The overall results were more hassle than the cost of the battery. For a forklift, well, it is different. I can definitely see that even if it has to live on the charger when not in use, if it will get one truck unloaded without quitting, it's likely to be usable to many folks with intermittent need for a forklift. Those batteries are expensive as heck.
 
batteries are getting expensive and charging devices even more so. whats the point of paying several times the price of a battery? and even then they will recover a batterey in certain instances only. (how do you know a battery is "sulfated")

cheap pulse chargers dont work. last time i hooked one up to a weak battery the battery was dead after the procedure.

btw, trickle chargers the same thing. after cheap ones killed a battery twice over the winter i dont touch them. hook up a 4amp charger once in while.
 
People have been trying to rejuvenate sulfated batteries for a long time. If anything really worked, we'd know about it by now. Some techniques may get a small amount of capacity back, but IMO it's a losing proposition in the long run. Because a fool is born every minute, new devices will keep coming.
 
Try nickel-iron instead? The damn things just won't die.

Hard to get, expensive, and don't hold a charge that long, but you can do almost anything except shoot holes in them and they will still charge up.
 
Try nickel-iron instead? The damn things just won't die.
Hard to get, expensive, and don't hold a charge that long, but you can do almost anything except shoot holes in them and they will still charge up.

That's an Edison cell. Alkaline electrolyte. Story: Edison was being interviewed in his lab. While the interview went on, there was a big crash outside the building. A man poked his hole in the doorway, and said "one story Mr. Edison." A while later there was a louder crash outside. "Two stories Mr. Edison."

They were testing the robustness of the batteries by throwing them out the window.
 
I have had limited experience with two methods.

first one was a standard car battery. it got to the point where couldn't keep the headlights on for 5 minutes or truck wouldn't start. Electrolyte was dumped out and replaced with water. Battery left on 1 amp capacity 13.8v float charger for 2 months. then left disconnected for 1 month. battery was placed back in my truck and i got another year of use out of it before it failed again, this time permanently. original electrolyte dumped out was 1.3 specific gravity. After 2 months of charging the specific gravity increased from 1, to 1.2. where the extra acid came from i have no idea, as i still have 3 quarts of 1.3SG acid from that battery.

my dad had a standard napa brand battery in his work van, lasted 6 years before its capacity reached merely 1 amp hour as tested. i reverse charged it. results weren't that good. after a few days of reverse charging i was able to discharge it and reach 20 amp hours capacity.

A battery from my brother's boat reached somewhat useless capacity over many years. we added some water, reverse charged it, measured its reverse capacity at 27 amp hours (1/3rd new capacity) and put it in my mom's jeep. it lasted 2 more years.


best result i had from reverse charging an AGM battery was a GNB 90 amp hour agm battery intended for permanent float charging. essentially designed to never be discharged but sit on a shelf in a government lab, or nuclear power plant. etc. this battery came from an oil refinery. it was completely open circuit, didn't draw current at all.
I cut the top of the battery off and added a bunch of water.
i tried charging it and discharging it with no improvment, then reverse charged it.
after 400 amp hours of current i was able to discharge it, and was able to pull 60 amp hours out of it.

after a dozen charge and discharge cycles its capacity quickly dropped to 30 amp hours, or about 1/3rd of nameplate capacity. this is typical of my many other experiments with permanently reversing the polarity of lead acid batteries.

I have not had any problems with the batteries failing suddenly or in a catastrophic manner when reverse charging.. except when i tried to reverse charge open circuit 5 amp hour sealed agm cells without adding water. you can dump a lot of amps into the battery "backwards" and then suddenly the battery gets really hot later.
 
I have a setup in our 5th wheel with 6 golf cart batteries and solar with inverter and I just bought a new set of Interstate batteries from Costco to replace the Trojan T-105's that aren't holding a charge very well and have specific gravity in the yellow/red zone.

What I've been thinking about doing is reverse charging them with a non automatic charger and seeing if it will do the same thing as I use to derust things with electrolysis. It sure seems like it would work the same way. I'm thinking of just hooking a pair of them up together and discharging them to zero volts with a light bulb and then reverse charging them. My dad told me years ago that it would work but I've never tried it.

BTW, I paid a little under a hundred each for the Interstate batteries a month ago and the Trojan's were 150 plus tax when I bought them about 5 years ago. I did major damage to the Trojan's a few years ago when I forgot that my inverter turns on automatically when I turn the battery switch on and I didn't get back to it for a week. They were under 1 volt and batteries don't like that.
 
im surprized epsom salt has not been mentioned.

btw, hooking up battery to welder (ac) didnt help. it killed it, if i remember correctly.
 
BTW, what do people do to batteries to kill 'em? I live in a northern climate and always get ten years plus from batteries before they get even slightly bad. Keep 'em topped up, even low maintenance types, don't let them get run down and keep the terminal areas clean.
 
BTW, what do people do to batteries to kill 'em? I live in a northern climate and always get ten years plus from batteries before they get even slightly bad. Keep 'em topped up, even low maintenance types, don't let them get run down and keep the terminal areas clean.

I think the main cause of killing batteries is letting them run down too far. That's how I killed mine. My inverter draws about 4 amps even when not using anything that is powered by it. I have an isolator that allows me to disconnect the batteries and forgot to isolate the batteries. It ran them down to less than one volt. Very bad on the batteries.

I got over 10 years out of the last set.
 
LVD
Low Voltage Disconnect.

Most better devices have this feature for that reason.

Even crappy things simply stop working when voltage gets low.

These are not that expensive in in some rv uses where contactor is not magnetic latching but normal active coil easy to add.

Magnetic latching requires a bit more work.

Sent from my SM-G781V using Tapatalk
 








 
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