I have an ~18 amp hour SLA battery that is in one of those portable jump start things. I've had it for about a year and a half, it's been mostly dead for most of that time. It works for a little while if I plug small devices into it, holding maybe 2 amp hours. If I try and jump start with it, it's worse than the battery I am jumping. When I charge it, it shows it's charged up within a few hours, should take around 12 hours. It was never abused very much, I have another one of these things that has just been beat to hell and it still works great. Is there anything I can do to try and "revive" the battery?
Is there anything I can do for a dead SLA battery?
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GJW
Flashlight Enthusiast
Usually not but we have had some luck with this:
AccuMate Charger
It's brought a few batteries back from the dead for us.
We bought ours from England but there are US distributors now.
AccuMate Charger
It's brought a few batteries back from the dead for us.
We bought ours from England but there are US distributors now.
What exactly does that thing do to help the batteries? I'm sure that's a nice charger, but if I had to buy something like that I would just get a new battery. Would it help to do something like give it alot of amps for a short time? Or higher voltage? Or something similar?
GJW
Flashlight Enthusiast
Nope, nope, and nope.
It's just a charger that's had some luck reviving a few batteries that wouldn't otherwise take a charge.
For 2 batteries it's probably not worth it but here we use hundreds.
It's just a charger that's had some luck reviving a few batteries that wouldn't otherwise take a charge.
For 2 batteries it's probably not worth it but here we use hundreds.
batterystation
Enlightened
What usually happens to SLA batteries is they dry up. They have lost their water. If this is the case, it is shot. SLA batteries also HATE to be stored in the "dead" mode. That will do them in too. If anyone has SLA/gel cell batteries on the shelf, CHARGE THEM while in storage on a monthly basis.
But how could this one have gotten that way in the first place? It wasn't very old when it stopped working, I might have discharged it completely once, and that's it. I have another just like it that is about 5 years old. I used to discharge it completely before charging it because I thought that was good for it. /ubbthreads/images/graemlins/smile.gif I have left it dead for months...overcharged it for days. Still will start up my boat just fine which need 1000 cranking amps minimum.
Brock
Flashaholic
Just unlucky I guess, or I should say lucky with the older one. Heres what I would do before I tossed it. Take in on you boat, once it's started and running connect it to the house or main battery and let it take the full charge from the alternator. It won't get any higher then any of the batteries on the system. Or if your boat is big and has a shore power charger you could turn that on and again connect it to the batteries. You could do this with a car, but it should be connected right at the battery and that is a LOT harder to drive and have it connected under the hood /ubbthreads/images/graemlins/wink.gif
Having said that the battery could leak or crack, or worst case even explode, but I would put odds of exploding about 10,000 to 1. Leaking on the other hand would be about 50 to 1. So if you can put the whole thing in a 5 gal pail, just in case, that is what I would do. Oh the odds that this might bring it back to life are about 1 in 8, maybe. Remember this is just my opinion and just what I would do, do so at your own risk. I will add that I have semi-revived a couple of SLA this way, about 1 in 8 /ubbthreads/images/graemlins/wink.gif
Having said that the battery could leak or crack, or worst case even explode, but I would put odds of exploding about 10,000 to 1. Leaking on the other hand would be about 50 to 1. So if you can put the whole thing in a 5 gal pail, just in case, that is what I would do. Oh the odds that this might bring it back to life are about 1 in 8, maybe. Remember this is just my opinion and just what I would do, do so at your own risk. I will add that I have semi-revived a couple of SLA this way, about 1 in 8 /ubbthreads/images/graemlins/wink.gif
LED_ASAP
Enlightened
One thing that worked for me was---scarey as it sounds---charge the battery with low voltage, low current AC power /ubbthreads/images/graemlins/grin.gif
My experience was with a tiny battery used in a Sony walkman, about 2V/1Ah. It won't hold power for more than 10 min playing time and I didn't want to fish out $70 to get a new one. So I hooked it up in series to a small 6V transformer and a ~5V/0.3A bi-pin bulb. Initially the bulb didn't lit at all, but after a few hours it started to glow and eventually got pretty bright. Then it was hooked to the walkman and it charged OK.
For your 18Ah battery, I think you need to find something that will handle a couple of amps, like the turn-signal bulb for cars, and hook it up to something like 16V AC(assume the battery is 12V).
Even if you can revive the battery to some extent, it won't perform as well as new batteries. Lead-Acid batteries won't be damaged by slight over charging, but will be seriously damaged if allowed to run flat. So charge them after each use, and once every 6 months or so if sitting on the shelf.
My experience was with a tiny battery used in a Sony walkman, about 2V/1Ah. It won't hold power for more than 10 min playing time and I didn't want to fish out $70 to get a new one. So I hooked it up in series to a small 6V transformer and a ~5V/0.3A bi-pin bulb. Initially the bulb didn't lit at all, but after a few hours it started to glow and eventually got pretty bright. Then it was hooked to the walkman and it charged OK.
For your 18Ah battery, I think you need to find something that will handle a couple of amps, like the turn-signal bulb for cars, and hook it up to something like 16V AC(assume the battery is 12V).
Even if you can revive the battery to some extent, it won't perform as well as new batteries. Lead-Acid batteries won't be damaged by slight over charging, but will be seriously damaged if allowed to run flat. So charge them after each use, and once every 6 months or so if sitting on the shelf.
i once recovered a badly sulphated gellcell from a ups that had been left on for 2 years by using 120vac!
used a 1n4007 and a 7w nightlight to charge it.
the higher voltage helped to break down the sulphation.
in your case i would get a new battery for the jump box and play with the old one.starting a car with a dead battery is a pretty demanding application for a small sla.
[ QUOTE ]
LED mods As Small As Possible said:
One thing that worked for me was---scarey as it sounds---charge the battery with low voltage, low current AC power /ubbthreads/images/graemlins/grin.gif
My experience was with a tiny battery used in a Sony walkman, about 2V/1Ah. It won't hold power for more than 10 min playing time and I didn't want to fish out $70 to get a new one. So I hooked it up in series to a small 6V transformer and a ~5V/0.3A bi-pin bulb. Initially the bulb didn't lit at all, but after a few hours it started to glow and eventually got pretty bright. Then it was hooked to the walkman and it charged OK.
For your 18Ah battery, I think you need to find something that will handle a couple of amps, like the turn-signal bulb for cars, and hook it up to something like 16V AC(assume the battery is 12V).
Even if you can revive the battery to some extent, it won't perform as well as new batteries. Lead-Acid batteries won't be damaged by slight over charging, but will be seriously damaged if allowed to run flat. So charge them after each use, and once every 6 months or so if sitting on the shelf.
[/ QUOTE ]
used a 1n4007 and a 7w nightlight to charge it.
the higher voltage helped to break down the sulphation.
in your case i would get a new battery for the jump box and play with the old one.starting a car with a dead battery is a pretty demanding application for a small sla.
[ QUOTE ]
LED mods As Small As Possible said:
One thing that worked for me was---scarey as it sounds---charge the battery with low voltage, low current AC power /ubbthreads/images/graemlins/grin.gif
My experience was with a tiny battery used in a Sony walkman, about 2V/1Ah. It won't hold power for more than 10 min playing time and I didn't want to fish out $70 to get a new one. So I hooked it up in series to a small 6V transformer and a ~5V/0.3A bi-pin bulb. Initially the bulb didn't lit at all, but after a few hours it started to glow and eventually got pretty bright. Then it was hooked to the walkman and it charged OK.
For your 18Ah battery, I think you need to find something that will handle a couple of amps, like the turn-signal bulb for cars, and hook it up to something like 16V AC(assume the battery is 12V).
Even if you can revive the battery to some extent, it won't perform as well as new batteries. Lead-Acid batteries won't be damaged by slight over charging, but will be seriously damaged if allowed to run flat. So charge them after each use, and once every 6 months or so if sitting on the shelf.
[/ QUOTE ]
Ray_of_Light
Flashlight Enthusiast
Add some sulphuric acid at 36 Be (Baume degrees, indicated a concentration of about 30 percent) and reverse charge the battery for half hour. (10 percent of battery capacity)
Start a normal charge then, and discharge the battery with a bulb, 12V 20 W.
Repeat the reverse charge up to three times. This should take the lead sulphate off the plates. If, after the third reverse charge, and a subsequent full normal charge, you do not get the full capacity, the plates are irrimediably destroyed ad you should discard the battery.
Anthony
Start a normal charge then, and discharge the battery with a bulb, 12V 20 W.
Repeat the reverse charge up to three times. This should take the lead sulphate off the plates. If, after the third reverse charge, and a subsequent full normal charge, you do not get the full capacity, the plates are irrimediably destroyed ad you should discard the battery.
Anthony
Brock
Flashaholic
The problem with leaving it sit on a charger, or overcharging it, is it is a sealed battery. You can't add acid, so overcharging it will cause it to vent gasses or leak. Once it's gone you can't add any back in. That is why I recommended charging it at a higher voltage, but in parallel with another 12v battery.
zmoz, the lawnmower charger should work, but might not since the SLA might be stable enough for the alternator to work correctly, but it's worth a shot.
zmoz, the lawnmower charger should work, but might not since the SLA might be stable enough for the alternator to work correctly, but it's worth a shot.
LED_ASAP
Enlightened
[ QUOTE ]
Brock said:
That is why I recommended charging it at a higher voltage, but in parallel with another 12v battery.
[/ QUOTE ]
No no, charging it parallel with a good battery will only cause that good battery to sink all the current as that is the lowest resistance pathway.
Brock said:
That is why I recommended charging it at a higher voltage, but in parallel with another 12v battery.
[/ QUOTE ]
No no, charging it parallel with a good battery will only cause that good battery to sink all the current as that is the lowest resistance pathway.
The_LED_Museum
*Retired*
If the plates are sulfated, you're probably SOL.
Lead sulfate is a spongy material that is nonreactive (it doesn't produce electricity, and cannot be charged up), and can form on the surface of the plates with as little as 24 hours of "dead" time. That's why you often see admonishments that you should never run a lead acid battery (especially a SLA battery) to the ground, and to charge it fully within 24 hours if you do discharge it significantly.
Now, I wasn't aware you could dislodge lead sulfate with AC or reverse-charging...usually when a battery becomes sulfated, you throw it away and get a new one.
Lead sulfate is a spongy material that is nonreactive (it doesn't produce electricity, and cannot be charged up), and can form on the surface of the plates with as little as 24 hours of "dead" time. That's why you often see admonishments that you should never run a lead acid battery (especially a SLA battery) to the ground, and to charge it fully within 24 hours if you do discharge it significantly.
Now, I wasn't aware you could dislodge lead sulfate with AC or reverse-charging...usually when a battery becomes sulfated, you throw it away and get a new one.
Brock
Flashaholic
[ QUOTE ]
No no, charging it parallel with a good battery will only cause that good battery to sink all the current as that is the lowest resistance pathway.
[/ QUOTE ]
This is true if you have a small underpowered charger, but it is a car alternator of larger marine alternator, I can assure you it will bring a weak battery up to voltage. It might not be good for the bad battery, but it will get it up to voltage.
No no, charging it parallel with a good battery will only cause that good battery to sink all the current as that is the lowest resistance pathway.
[/ QUOTE ]
This is true if you have a small underpowered charger, but it is a car alternator of larger marine alternator, I can assure you it will bring a weak battery up to voltage. It might not be good for the bad battery, but it will get it up to voltage.
Sorry for activating an old thread, but I think it's better than opening a new one. I have a one year old SLA 12V 7.5 Ah battery. I use it only during summer to power up a portable audio system with car radio and speakers on the beach. So, during winter, it was not used. Today I tried to charge it but it won't charge. I meassured a 5.5V voltage on it (instead 12V) and when I connect it to power source (up to 21 V) with ampermeter in series, it meassures 0.00 A. Is there anything I can do to recover it!? It's only 1 year old and it served only 1 summer.
I have another SLA 12V 4.5 Ah for 4-5 years now which I was using for that same purpouse and it's still alive! It was not used during winter as well and it was barely used last summer since I had this 7.5 Ah one and today I connected it to car radio and it works. I'm charging it currently. So how is this possible that a 4-5 years old battery still works and this new one is already dead? Both batteries have been used on the same way.
I read all posts in this topic but there are different and oposite advices so I don't know what to do now. Any advice is welcome. I found this video: http://makezine.com/2013/03/27/how-to-recover-a-sealed-lead-acid-battery/ and my battery looks the same as this one in the video, but from another manufacturer. Will this work?
I saw that there are some chargers that can recover batteries but buying them is not profitable since the battery costed less than 20$. Is cheaper to buy a new one. So my question is mostly related to a way of recovering it without buying an aditional equipment.
EDIT: I tried to keep it connected on the power source and it's voltage vent from 4.83 to 6 V but all that time, there was NO current flowing to the battery. I put ammeter to micro ampers but there is still a big zero standing. I tried ammeter with another battery, it works. I tried to connect a LED diode to the battery and it's barely working, while it's connected, the voltage of the battery drops to 1.6 V and when I remove the LED, it went back to 5.6 V.
I have another SLA 12V 4.5 Ah for 4-5 years now which I was using for that same purpouse and it's still alive! It was not used during winter as well and it was barely used last summer since I had this 7.5 Ah one and today I connected it to car radio and it works. I'm charging it currently. So how is this possible that a 4-5 years old battery still works and this new one is already dead? Both batteries have been used on the same way.
I read all posts in this topic but there are different and oposite advices so I don't know what to do now. Any advice is welcome. I found this video: http://makezine.com/2013/03/27/how-to-recover-a-sealed-lead-acid-battery/ and my battery looks the same as this one in the video, but from another manufacturer. Will this work?
I saw that there are some chargers that can recover batteries but buying them is not profitable since the battery costed less than 20$. Is cheaper to buy a new one. So my question is mostly related to a way of recovering it without buying an aditional equipment.
EDIT: I tried to keep it connected on the power source and it's voltage vent from 4.83 to 6 V but all that time, there was NO current flowing to the battery. I put ammeter to micro ampers but there is still a big zero standing. I tried ammeter with another battery, it works. I tried to connect a LED diode to the battery and it's barely working, while it's connected, the voltage of the battery drops to 1.6 V and when I remove the LED, it went back to 5.6 V.
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more_vampires
Flashlight Enthusiast
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Storage condition and maintenance. Example: Store the battery touching the ground = killed battery. ...so don't put the battery onto the floor or ground. Lots of one-off situations that can do it. Excessive temperature extremes, thermal cycling, on and on...
Also, you don't know how long a recently purchased battery has been on the shelf. Big difference from "actually new."
WalkIntoTheLight
Flashlight Enthusiast
They come in a plastic housing. How is putting it on the ground going to drain it?
more_vampires
Flashlight Enthusiast
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Old mechanics with gray hair told me about this. Apparently, it's a bad practice according to the old heads. The conventional wisdom says you can put a NON FILLED battery on the floor, no problem. I've been yelled at about this in various shops over the past 20 years.
Electrical continuity is one thing, but magnetic fields are another issue. From what I understand, magnetic fields can mess with a battery as well over long term periods. The Earth is the ultimate grounding force. Burying a battery will kill the crap out of it, afaik.
It's quite possible all of these old mechanics with gray hair are full of it, repeating an "old mechanic's superstition tale." It's been drilled into my head, however.
Wonder if it's actually true or a load of BS? Can anyone confirm or deny? I'd actually like an authoritative confirmation or denial.
Electrical continuity is one thing, but magnetic fields are another issue. From what I understand, magnetic fields can mess with a battery as well over long term periods. The Earth is the ultimate grounding force. Burying a battery will kill the crap out of it, afaik.
It's quite possible all of these old mechanics with gray hair are full of it, repeating an "old mechanic's superstition tale." It's been drilled into my head, however.
Wonder if it's actually true or a load of BS? Can anyone confirm or deny? I'd actually like an authoritative confirmation or denial.
