Yes, this guy is giving really bad advice. You can’t mistreat li-ions and then trust them.
aging li-ion cell risk at DuckDuckGo
DuckDuckGo. Privacy, Simplified.
Yes, this guy is giving really bad advice. You can’t mistreat li-ions and then trust them.
I used a 12v/5v power supply that I made using an old Xbox 360 power brick though. You mean 12v is too much even for 3 seconds?
What do you think is happening inside the li-ion cell when you push 12 volts through it?
What I understood from that site was to only tap quickly 3 times and it’ll jump start the battery. I guess 12v is a no no by the looks of it. So next time when trying to jump start a malfunctioning battery, both batteries needs to be the same brand and voltage??
I’ve heard of doing this with the old NiCad batteries. Something about the dendrites forming within the cells and shorting them out. Supposedly short pulses with high amps melts the dendrites and they work (kinda) for a while longer.
Well the Ternergy before jump start has 0v. After jump start, it worked in the flashllight. When I then charged it, it was stuck at ~5oom mA. It hasn’t changed values in the last 30 mins.
The 14500 is still working good in the flashlight.
Hank33: what do you think is happening inside the cell when you push 12v through it?
This is not handwaving magic, it’s chemistry.
You can look this stuff up. Is any of this unfamiliar to you?
Here, let me quote a bit from one of those results:
There are two chemicals separated by a thin membrane.
What is the membrane in the specific battery you’re messing with? How would you know what’s inside the cell?
Crystals grow in one of the liquids and eventually a crystal “dendrite” can poke a hole in the membrane. “Zapping” the cell may disintegrate the dendrite but leave the hole poked in the separator.
Then you get leakage through the hole.
Chemistry. It has rates of change.
You may also find this helpful: https://www.simsrecycling.com/2019/05/23/guide-how-to-responsibly-dispose-of-lithium-ion-batteries/
Don’t panic. We’ve all had to learn this stuff.
I’ve had two li-ion cells vent their contents — one while on a charger, and the other while in my fireproof metal storage box.
That’s over the quite a few years I’ve had them in the house. Fortunately neither of them caught fire and set off the surrounding cells; I just found the chemical stain around the anode ends and on the surrounding material when I checked them later.
Great power, great responsibility.
I revived a 0.0 Volts Aspire 18350 by tapping it with 12 Volts from an somewhat tired, elderly Lead-acid battery a couple months ago.
NOR test revealed it’s 1130 (iirc) mAh, which is even a bit more than when it was new (before ‘break in’).
It was quite a bit more than 3 taps though, before it got up to 2.5 Volts.
Ah…
Hmmm…
So i have a ticking time bomb now, perhaps…
Makes sense though: melt down the dendrites, leave holes…
That NIH paper linked above says
The tendency of particle penetration through the separator and the formation of dendrites during over-charging are very high in the Li-ion system.
Here are some of the materials used as separators.
So if I have some older cells that I’ve taken care of that still work fine in flashlights can they catastrophically fail due to aging just sitting there, not on a charger? And does this apply to IMR’s also? Just asking, I have lots of batteries from the first wave of flashlights from the mid 2000’s…
Rich
can they catastrophically fail due to aging just sitting there, not on a charger?
Good question, much discussed. We’re part of a great experiment.
DuckDuckGo. Privacy, Simplified.
Don’t squeeze them: Lithium-Ion Batteries Are a Literal Trash Fire, and Getting Worse | iFixit News
I’ve heard of doing this with the old NiCad batteries. Something about the dendrites forming within the cells and shorting them out. Supposedly short pulses with high amps melts the dendrites and they work (kinda) for a while longer.
That’s why I stressed in the original thread to use big caps to hit ’em with. A few thousand µF charged to 12V or whatever is like rapping the end of a jar’s cap to loosen it, not bashing it with a sledgehammer to bust it into pieces.
Zathras warn, but no, no one listen to poor Zathras, no.
you can also (yet another way to implement what is a bad idea) just take a cell that is good, and parallel it briefly to a ‘bad’ one.
the good one will try to charge the bad one, the volts will not be too high, and it might get over the voltage where a charger would try to charge it
bad idea though because an overdischarged li ion may have formed the dreaded ‘dendrites’ internally.
if so, there will be partial shorts between anode and cathode that may totally short under charge OR load, and flame the cell up
to the chagrin of your pocket neighbors, ie, your ‘junk’
or a bunch of other cells in storage or in the charger, ie ‘huge fire at home’
so don;t do that!
but at least it isn’t 12v
wle
you can also (yet another way to implement what is a bad idea) just take a cell that is good, and parallel it briefly to a ‘bad’ one.
the good one will try to charge the bad one, the volts will not be too high, and it might get over the voltage where a charger would try to charge it
bad idea though because an overdischarged li ion may have formed the dreaded ‘dendrites’ internally.
if so, there will be partial shorts between anode and cathode that may totally short under charge OR load, and flame the cell up
to the chagrin of your pocket neighbors, ie, your ‘junk’
or a bunch of other cells in storage or in the charger, ie ‘huge fire at home’so don;t do that!
but at least it isn’t 12v
wle
That’s called the jump or the paper clip method , that’s ok for protected lithium iron cells when the protection has tripped due to going below 3volts & certain chargers can’t recognise it ,also it’s ok for nimh @ 0volts.
Remember Rule One for dealing with a li-ion battery fire:
Don’t Inhale.
https://www.nature.com/articles/s41598-017-09784-z
An irreversible thermal event in a lithium-ion battery can be initiated in several ways, by spontaneous internal or external short-circuit, overcharging, external heating or fire, mechanical abuse etc. This may result in a thermal runaway caused by the exothermal reactions in the battery6,7,8,9,10, eventually resulting in a fire and/or explosion. The consequences of such an event in a large Li-ion battery pack can be severe due to the risk for failure propagation11,12,13. The electrolyte in a lithium-ion battery is flammable and generally contains lithium hexafluorophosphate (LiPF6) or other Li-salts containing fluorine. In the event of overheating the electrolyte will evaporate and eventually be vented out from the battery cells. The gases may or may not be ignited immediately. In case the emitted gas is not immediately ignited the risk for a gas explosion at a later stage may be imminent. Li-ion batteries release a various number of toxic substances14,15,16 as well as e.g. CO (an asphyxiant gas) and CO2 (induces anoxia) during heating and fire. At elevated temperature the fluorine content of the electrolyte and, to some extent, other parts of the battery such as the polyvinylidene fluoride (PVdF) binder in the electrodes, may form gases such as hydrogen fluoride HF, phosphorus pentafluoride (PF5) and phosphoryl fluoride (POF3). Compounds containing fluorine can also be present as e.g. flame retardants in electrolyte and/or separator17, in additives and in the electrode materials, e.g. fluorophosphates18,19, adding additional sources of fluorine….
Emphasis added.
Update
I’m sad to say that the Sofirn 14500 batt is now kaput! After I zapped it, it worked and so off it went to storage. Today after trying it, it’s a no go. RIP
Hmmm, maybe the coronavirus got it…
It could happen fast and silent or slow and painful. I think somebody up there likes you.