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Lithium Ion recharge from 'death'

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Sceadwian

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I have a laptop battery that would no longer properly charge and gutted the cells from it, they're Sony 2200mah cylindrical Lithium Ion cells. Most of the cells read 1.4-1.9 volts or so, two read .9 I can guarantee the .9 volt cells are unusable but I don't know anything about the charging circuitry and why it was cutting off. Anyone have any experience trying to recharge lithium ion cells that have reached this state and been there for quiet a bit? I'm going to hand charge one of the better cells using a low constant current monitoring for temperature but I don't know what happens to the chemistry of a battery that's been in such a state for a long period of time, other people's experience would be useful.
 
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The Battery University on the web or other sites explain that a Lithium rechargeable battery cell that has its voltage drop to less than about 3.0V is being destroyed by Lithium ions plating into solid lithium metal and the destruction can only partially be reduced by very low current charging until the voltage is above about 3.2V.
Your cells at only 0.9V to 1.9V are destroyed.
The battery is supposed to have a protection circuit in it that cuts off the load when the voltage drops to less than about 3.2V per cell.
 
If the battery wouldn't charge, it's likely that it died due to old age or too many cycles. Although some of the cells may be better than others, they're probably all in a really bad way so not worth doing anything with.

The charger would have cut off when any cell voltage was too high or any temperature was too high. If a cell was too low, the charging should have been slow until it picked up to 3.2 or so, but the circuit may have timed out if that didn't happen reasonably quickly.

However, a lot of battery management circuits are programmed to disable the battery if they think it has been abused, so there may be little wrong with it.

(Close the lid on a MacBook and leave it for a month and it costs you a new battery, even though all the cells can be charged OK. Turn it off, close the lid, and leave it for a month and it's fine.)
 
I pulled a laptop battery cell or two apart years ago and the lithium ion batteries are still going, they do provide the voltage for the electronics on my cnc and all I do to charge them is use the smart charger I built about 5 years ago. I have done an experiment on them, put one down a rabbit hole with reverse voltage and stand back when the power is applied......
 
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Protection circuitry disconnects between 2.4v-2.8vdc to prevent overdischarge. The disconnect voltage setting varies between manf. depending on device's peak current drain to allow for battery Rs voltage drop under heavy loading.

When battery is less then 3.0v the charge rate should be limited to <0.1C until voltage rises to about 3.4vdc.

Lithium cells less then 1.5v likely develop dendrites and recharge should not be attempted.

Most laptop battery packs have an eprom that gets a permanent disable bit set when a bad cell is detected. Changing out the bad battery or even all batteries does not revive battery pack because of the eprom disable. There has been some info on some types of packs that discuss how to reset eprom disable bit but it varies between different manf.
 
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No intention of using the pack whole again so I could care less about resetting an eeprom, it's been sitting at that low voltage for too long, from what I'm reading it's probably better to just recycle them. I have 4 other cells from a different pack of the same type that are in known working order, was just wondering if anyone had succesfull gotten cells that had been overdischarge to that extent back working again.
 
My electric RC model airplanes use Li-Po battery cells. The motor begins to pulse as a warning when the voltage drops to about 3.2V but if the airplane is too high then I don't notice the reduction in power and I keep flying until the motor stops when the battery voltage drops to about 3.0V.
If the original battery is discharged to 3.0V about 20 times then its capacity is reduced so much that it is useless. I have 11 useless battery cells.
Those battery cells are Generation-3. I ordered new Generation-4 battery cells (they are better and less expensive) and they have more power for a longer duration and they do not reduce their capacity when they are discharged low many times. Each cell has been used at least 50 times and their performance is still like new.
 
The new cells you have probably have some kind of built int thermal/voltage limiting system, they've come a long way. I'm not talking a full charge monitoring system like the electronics provide, just a built in safety net that helps balance a series pack.
Lipos are really only a problem when they're in a series pack, because the battery monitor circuit can't monitor each cell individually (I've never seen one in typical commercial devices at least), once a single cell is overly stressed in flight it will just get worse ultimately leading to the end of the pack, one of those cells eventually becomes a resistor. Even in the best of modern manufactoring facilities and using cells from a batch run, the chemistry ALWAYS has a lot of variation.

AG I'm guessing you're using a 3-7 cell series pack, possible in parallel?? You need better electronics in your plane, such as voltage monitoring systems that will monitor each cell and cut the whole pack off if any cell comes even close, or at least automatically lower the power level to allow the cells voltage to recover slightly, that will give you a gradual automatic power fade away that is bullet proof electrically.
The only problem is you have to monitor the specific voltage of EVERY cell in the pack simultaneously, not too hard with proper electronics knowledge, but definitely not a weekend project.

Even without any of that additional stuff set the cuttoff voltage to 3.4 volts on your current setup and you'll get at least 25% more charge/discharge cycles out of the same pack.
 
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My Piper Cub RC airplane uses 3-channels and weighs 1.0oz (28.3 grams) with the single-cell Li-Po battery cell. It flies for about 10 minutes to 15 minutes per charge. It can do loops. The battery weighs 3.8 grams (120mAh) or 4.1 grams (160mAh).
My P-51 Mustang is 4-channels with ailerons and weighs 1.2oz (34.6 grams) with battery. It can climb vertically and can do fast rolls. It flies for 6 minutes to 12 minutes per charge.
The two airplanes and my new helicopter use the same transmitter and battery cells.
 

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I have a laptop battery that would no longer properly charge and gutted the cells from it, they're Sony 2200mah cylindrical Lithium Ion cells. Most of the cells read 1.4-1.9 volts or so, two read .9 I can guarantee the .9 volt cells are unusable but I don't know anything about the charging circuitry and why it was cutting off. Anyone have any experience trying to recharge lithium ion cells that have reached this state and been there for quiet a bit? I'm going to hand charge one of the better cells using a low constant current monitoring for temperature but I don't know what happens to the chemistry of a battery that's been in such a state for a long period of time, other people's experience would be useful.

They are definitely dead!

Did you ever hear of the recall of sony lithium batteries?
 
Yeah, I've heard of a couple Sony battery recalls and a few from others as well, what's that got to do with this though? Are you saying the cells they shipped were dead on delivery?
 
No it's for nothing carmusic. The pack was from a laptop, I recycle all the old electronics I can get my hands on, I don't have a lot of active projects going right now but it's going eliminate a lot of bills and satisifies my natural curiosity to identify the useful bits out the stuff I take apart and store it for when I have a bit more space, and play with when I'm bored. Most people just throw this stuff out and I have hundreds of dollars if not more in discretes and small modules that would otherwise end up in a landfill that still work fine. As far as the batteries go I have a collection going that I'll be taking back to a recycling center when it's too big for the drawer it's it.
 
Old saying "suck it and see" Dont talk about it do it.

Some of these cells come back as good as gold ,most are just dead.The rabbit hole idea sounds like fun so I would choose the worst and bung it in a hole.

I once cut a 9V battery down the middle sideways to photograph for a Uni assignment. Taught me a bit too.
I have never come accross an eprom in battery packs so I will go google and see
 
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