18650 battery feels consistently hot and reading way over 4.3 volts?

snakebite · 2018-04-08T17:45:31.000Z

only way i can see that cell reading 9.xx v is on a harbor freight meter with a low battery.
they can be wildly inaccurate when the battery is low.
the heat is damage to the charger/protection board.
i would take it off and convert it to unprotected.
cell is likely fine.

Valharth1031 · 2018-04-09T00:34:54.000Z

Update: Over the course of the few hours, voltage has gone down and now reads 9.68.

Valharth1031 · 2018-04-09T00:37:09.000Z

Barkuti:

WalkIntoTheLight:

… that battery is waiting to vent or flame or even explode. 9.96v sounds impossible …

Most of the vent and flame thing with li-ion is exaggerated gossip, I think. If you read Intertek’s guide to the UN requirements for lithium battery testing prior to transportation, in page 9 you can see the overcharge test for single li-ion cells implies “2x voltage and current” for 24 hours, with a “no disassembly or fire within 7 days of test” pass criteria. Serious benchmark!

And you know… well, everything’s possible I believe.

Cheers :partying_face:

Good to know that it’s exaggerated. Made me a bit paranoid that it would blow up in my face any moment. lol.

Valharth1031 · 2018-04-09T00:39:43.000Z

snakebite:

only way i can see that cell reading 9.xx v is on a harbor freight meter with a low battery.
they can be wildly inaccurate when the battery is low.
the heat is damage to the charger/protection board.
i would take it off and convert it to unprotected.
cell is likely fine.

I’ll consider this. It would seem like a waste to just throw it out willy-nilly.

Danglerb · 2018-04-09T01:08:44.000Z

All my funky cells go to the local hazardous material waste site. They take old electronics, engine oil, paint, etc.

I would be concerned about how it got to over 4.2v, that makes me think there is a charging issue.

No I would not keep it, at least as is, maybe if the protection circuit was removed.

Barkuti · 2018-04-09T01:19:57.000Z

If those measured voltages are right (9.96V, then 9.68V after a few hours means damaged cell), such cell should be disposed. I've seen cheap 4.2V cells die just by overcharging them up to ≈4.35V. It's not worth taking a risk in this case.

Cheers ^:)

d_t_a · 2018-04-09T02:04:50.000Z

for reference comparison, Samsung 30Q specs PDF indicates it undergoes factory stress tests by overcharging to 20v:

“Level 1”: battery damaged (leaks), but doesn’t explode…

moderator007 · 2018-04-09T02:17:43.000Z

It’s toast and to cheap to replace to risk burning your house down. Dispose of the cell and replace it.

RobertB · 2018-04-09T02:24:57.000Z

Toss it in a bucket of saltwater solution, and set it outside for a couple days. It should be good and dead by then.

bansuri · 2018-04-09T02:32:44.000Z

If the instruments you’re measuring these batteries with consistently measure other known voltages accurately; please do not sleep in a residence with this battery in it.
Easy enough to read less voltage from a battery, requires a specific circuit to put out a reading at 2X what you’re expecting.
There may be special circumstances but if the battery was “quite a bit hot as I got it out of my MH20, which btw was off and not in use for hours” there’s a problem.

thijsco19 · 2018-04-09T04:51:39.000Z

Valharth1031:

snakebite:

only way i can see that cell reading 9.xx v is on a harbor freight meter with a low battery.
they can be wildly inaccurate when the battery is low.
the heat is damage to the charger/protection board.
i would take it off and convert it to unprotected.
cell is likely fine.

I’ll consider this. It would seem like a waste to just throw it out willy-nilly.

Don’t risk it. I wouldn’t trust a cell like this anymore.

If you want a unprotected cell just buy one they are pretty cheap.

WalkIntoTheLight · 2018-04-09T13:10:14.000Z

d_t_a:

for reference comparison, Samsung 30Q specs PDF indicates it undergoes factory stress tests by overcharging to 20v:

I’m not sure that test indicates the cell is charged up to 20v. It may just be that they use a 20v load on it in order to force current through it to overcharge it. Can a lithium-ion cell even have a resting voltage more than about 5v?

nick779 · 2018-04-09T13:26:31.000Z

RobertB:

Toss it in a bucket of saltwater solution, and set it outside for a couple days. It should be good and dead by then.

This.

a $10 cell is hardly worth the risk

DB_Custom · 2018-04-09T14:27:36.000Z

Batteries Plus, or anyplace like that, will take the discard cells.

DO NOT toss it in the saltwater solution like Robert B said! BAD ADVICE!

I’d remove the wrapper and cut the protection circuit, see if it stays a problem with the protection circuit disabled. If it seems fine then I’d remove the protection stuff and re-wrap it, keep an eye on it in use in a regular flashlight and see how it goes.

moderator007 · 2018-04-09T15:29:31.000Z

If the resting voltage is 9.68 volts like the op stated above what use is it. If he sticks it in a flashlight it could fry his driver or give to much current from the higher voltage and go “POOF”.
I=V/R
His over twice the normal voltage. You might try removing the PCB but I don’t think the circuit can boost twice the voltage. Far as I know it’s just a simple controlled FET switch.

CRX · 2018-04-09T15:44:03.000Z

Single cell XHP70 light?

moderator007 · 2018-04-09T15:50:55.000Z

CRX:

Single cell XHP70 light?

That will work direct drive. Might be the worlds brightest single cell XHP70 for a few seconds.

Couchmaster · 2018-04-09T19:51:44.000Z

HarleyQuin:

I wouldn’t trust Nitecore to have used only cells from quality brands. I wouldn’t trust shady chinese cell makers (there are tons of them) to produce anything that passes regulated tests…

Not sure I’d consider Nitecore shady. Do you have evidence of any shady issues Nitecore has engaged in?

As far as that goes, it’s far more likely to be a fake Nitecore. That is, some Chinese guy is recycliing used laptop batteries and has 200,000 Nitecore wrappers to use up. Nitecore chargers have been and are being counterfeited. (see links below) The OP received it as a gift so we cannot even authenticate the purchased location.

https://budgetlightforum.com/t/-/37563
http://www.candlepowerforums.com/vb/showthread.php?424302-Fake-Nitecore-Chargers-even-in-very-big-stores-D4-and-others

HarleyQuin · 2018-04-09T20:16:59.000Z

Couchmaster:

HarleyQuin:

I wouldn’t trust Nitecore to have used only cells from quality brands. I wouldn’t trust shady chinese cell makers (there are tons of them) to produce anything that passes regulated tests…

Not sure I’d consider Nitecore shady.

I did not say that.
Nitecore is not a cell maker.

I said I don’t trust Nitecore to use only quality brands. I’ve seen better brands than nitecore (and worse) using dubious chinese cells under the wrapper.
And I said I wouldn’t trust shady chinese cell makers. I very much stick to that as well.

It’s completely useless to know that a Samsung 30Q is rigorously tested, as long as we don’t know what is inside OP’s device.

I doubt Li-Ion chemistry can provide these 9V, so odds are the circuit is broken. What that is doing or has done to the cell, we don’t know until it’s tested. A damaged circuit might constantly drain the cell. Underdischarging will damage the cell.

OP’s device seems damaged anyway. I’d take the device outside the house, open it, remove the circuit and test the cell. Out of curiosity. Just to see which resting voltage it has. Then I’d remove the wrapper to see what nitecore was using. Then I’d bin it anyway and buy me a new Samsung 30Q from a reputable source. Or any other cell or device I want to use.

snakebite · 2018-04-14T12:49:53.000Z

i still fail to see how a cell goes to 9.xx v from a charger fed from 5v and through a linear regulater charging chip.
unless its plugged into usb3 on a pc or fancy phone charger and something went wrong there.
but these are long shots.