Reconditioning dead batteries: is this for real?

Old 10-25-17, 11:46 AM
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Reconditioning dead batteries: is this for real?

I spent a half hour watching a video about a way to recondition dead batteries. Including cordless tool batteries. Google recondition dead batteries and you can find the same video. You can buy the secret for $47.00
I remember the adage, if it sounds too good to be true. . .
Anybody have experience with this? Can if be for real?
Old 10-25-17, 12:55 PM
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There are several of those on YouTube. I bit on one a few years back although it was only about ten dollars as I recall. In a nutshell it told you to use a high-amperage battery (car battery or alarm system battery) and connect it in parallel with the bad battery. Only leave it connected for a maximum of three seconds and then charge as normal.

It is supposed to "reform" any cell that has had a spontaneous polarity reversal. It states that a bad cell will cause the battery to deplete itself in a matter of hours and then tells you to click on another link where (for an additional fee) they will tell you how to take the battery apart and replace the bad cell.

Save some money and learn from my mistake.
Old 10-25-17, 01:04 PM
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Thanks for the information
Old 10-25-17, 01:36 PM
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I remember something about this as well. It was supposed to "burn off" the little whiskers that could grow in the batteries and cause the cells to discharge. Pretty much sounded like junk science to me. Seems like you would want much higher voltage and low amperage to do that. But what do I know.
Old 10-25-17, 01:38 PM
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A lot depends on what kind of battery you want to resurrect. Wet cell lead acid batteries can sometimes be brought back using a desulfator. This only works on lead batteries that have died because of sulfation. Cordless tools use different chemistries like NiCad, MiMh, and a couple types of lithium. Some lithium packs can be brought back after the pack has been discharged too far and the charger calls it a bad battery.
Old 10-25-17, 07:44 PM
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I have had some success with the technique, but it is no secret. I hit the battery with a voltage higher then what the battery is rated for (EX: hitting a 18 volt battery with 24 volts) but the results are only temporary.
Old 10-26-17, 03:01 AM
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PT Barnum lives on even in the modern age.
Old 10-26-17, 10:14 AM
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Not all batteries go tango uniform for the same reasons, so the fact that it claims to work on all of them is a pretty good indication it's hokum.

RE: tool batteries, if you haven't tried it, I have found one free trick that does work. I don't remember where I read this but I tried it and gollygeewillikers, it revived my dead batteries.

I've got about half a dozen consumer-grade Ryobi 18v rechargeable battery power tools and four Li-Ion batteries, that often sit for months unused. Then when I get around to needing them, the battery is dead. Not flat, ...dead. When I put it on the charger, I get both the yellow and green lights, which means defective battery. I can leave them on the charger until doomsday and they won't take a charge.

But if I unplug them from the wall outlet and re-plug them repeatedly, eventually I get a red light, which indicates they're charging. I can never predict how many times I'll have to unplug/re-plug them; sometimes it's 10, sometimes it's 50, sometimes a hundred or more. I put the heel of my hand on the wall next to the outlet and jab the plug at the outlet rapid-fire so I get it done as quickly as possible and keep it up until I get the green light. But I've been doing this for several years and it ALWAYS works.

The first time it's "revived" it only takes a shallow charge but if I keep using them regularly, drawing them down through use and recharging them every day or so, in a few charging cycles the capacity is pretty good. I can't say it's good as new because I've had these too long to have any recollection of what "new" was like, but it's good enough that they have a useful life.

Then they sit unused for six months and go stone dead and I have to start from scratch again.

Removing and re-inserting the battery in the charger doesn't accomplish the same thing, you have to unplug/replug the charger. Dunno how many other chargers it'll work for but it works a charm for my Ryobi.
Old 10-27-17, 07:43 AM
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Decades ago I read in Popular Electronics that a NiCd battery could often be revived with a short high-current pulse & they recommended using a large capacitor to "spike" the battery. It works. Most people just spike it by tapping a jumper on a car battery. Little risky but it also works. Sometimes you can't even access the terminals in a battery pack--for those I suppose Fred's tip will work as long as the charger is connecting the battery to current for a short period while it diagnoses the battery condition. Eventually enough voltage is pumped into the battery for it to read "healthy" by the charger. In those cases I doubt the cells ever had an actual internal short. They were probably healthy but were discharged so low the "smart" charger thought it was defective.

I have rescued packs from the recycling bin in stores (with permission) and brought them back to life. These "smart" chargers are so conservative (Liability concerns) that they doom packs to an early grave.
Old 10-27-17, 08:55 AM
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You can jog them a little bit and gain a bit of extra life, but ultimately the chemistry changes over time and recycling is the only option. The exact reactions are different for each type of battery, but they all degrade over time to a point of being useless.

Chargers are often designed to reject the pack when it starts to get low to avoid a dangerous charge situation. This is especially true with lithium batteries as bad charge can cause a fire.
Old 10-28-17, 06:55 AM
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I had a couple of NiCad power drill batteries that would no longer take a charge. I jolted them with a power converter and checked them with a volt meter. One battery never came back to life. The other battery was revived and I checked it with a volt meter. It's charge was decent but it didn't run very long before requiring another zap.

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