Ebay China 18650 Zero volts suddenly (from 3.7V). Expected?

[Ouchyfoot]

Don’t cherry pick your quotes.

[Angler]

@Ouchyfoot

We want to promote LiIon safety and care. A few scare tactics are good to make sure the reader pays attention, but you shouldn’t be frightened.

The chemistry of today’s cells are much more stable than in the past. Take precautions and don’t mistreat your cells. Mostly, try to stick with major noted brands from Japan and Korea purchased from a known and trusted vendor and you should be just fine.

I personally would be concerned about an 89cent cell, specifically how was it produced so cheaply, or more specifically is it an example of a not todays chemistry cell, pulled out of a trash bin and rewrapped. Does it have any modern protections afforded to todays cells. Ouchyfoot would you feel safe using that and storing it in your home, knowing nothing more about it than it’s 89cent cost? I would advise anyone against this, since it is most likely not an example of the modern cell that you described. That is why I only quoted a single line from your post.

[Ouchyfoot]

I specifically stated to use only major noted Japanese and Korean brands from trusted vendors.
Don’t twist my words.

[FlashKat]

I own several NCR18650B batteries without protection.

@light-wolff

@Angler

@FlashKat

Where is a video shorting out a name brand battery?

I’m sure you can find one on Youtube using the search function there.
Here you go, the venerable Panasonic 18650

https://www.youtube.com/watch?v=A9F75XuGz7Q

Interesting video. The most interesting part is: how did he get an NCR18650B without a PTC? One can’t just remove the PTC from a cell that has one.

Shorting out cells with PTC is rather boring. They don’t even get hot. That being said, cheap noname chinese cells don’t have a PTC. Nor a CID, nor any other internal protection feature. Luckily, their capacity and current performance usually is so low that they don’t vent even in a dead short. I’ve tried that a few times.
A bigger danger is an INTERNAL short due to lack of quality control (as Angler pointed out). At an internal short, all the current goes through a very small area (where the defect is), so it can reach separator breakdown temperature and then ignition temperature there. At an external short the current (and thus temperature) is (more or less) evenly distributed over the whole cell.

[Angler]

@Ouchyfoot

I specifically stated to use only major noted Japanese and Korean brands from trusted vendors.
Don’t twist my words.

But he is not using one of those, yet you told him not to be frightened.

[Angler]

@FlashKat

I own several NCR18650B batteries without protection.

@light-wolff

@Angler

@FlashKat

Where is a video shorting out a name brand battery?

I’m sure you can find one on Youtube using the search function there.
Here you go, the venerable Panasonic 18650

https://www.youtube.com/watch?v=A9F75XuGz7Q

Interesting video. The most interesting part is: how did he get an NCR18650B without a PTC? One can’t just remove the PTC from a cell that has one.

Shorting out cells with PTC is rather boring. They don’t even get hot. That being said, cheap noname chinese cells don’t have a PTC. Nor a CID, nor any other internal protection feature. Luckily, their capacity and current performance usually is so low that they don’t vent even in a dead short. I’ve tried that a few times.
A bigger danger is an INTERNAL short due to lack of quality control (as Angler pointed out). At an internal short, all the current goes through a very small area (where the defect is), so it can reach separator breakdown temperature and then ignition temperature there. At an external short the current (and thus temperature) is (more or less) evenly distributed over the whole cell.

The PTC is not the protection board. It is an internal part of the cell safety mechanism, not removeable. To my knowledge these cells without PTC are only made for Tesla.

[Ouchyfoot]

@Angler

@Ouchyfoot

I specifically stated to use only major noted Japanese and Korean brands from trusted vendors.
Don’t twist my words.

But he is not using one of those, yet you told him not to be frightened.

You’re cherry picking my quote again.

Unsubscribed

[Angler]

@Ouchyfoot

@Angler

@Ouchyfoot

I specifically stated to use only major noted Japanese and Korean brands from trusted vendors.
Don’t twist my words.

But he is not using one of those, yet you told him not to be frightened.

You’re cherry picking my quote again.

Unsubscribed

@Angler

Ouchyfoot would you feel safe using that and storing it in your home, knowing nothing more about it than it’s 89cent cost?

Likewise you are cherry picking the parts you reply to.

[FlashKat]

oops!!! My mistake.

@Angler

@FlashKat

I own several NCR18650B batteries without protection.

@light-wolff

@Angler

@FlashKat

Where is a video shorting out a name brand battery?

I’m sure you can find one on Youtube using the search function there.
Here you go, the venerable Panasonic 18650

https://www.youtube.com/watch?v=A9F75XuGz7Q

Interesting video. The most interesting part is: how did he get an NCR18650B without a PTC? One can’t just remove the PTC from a cell that has one.

Shorting out cells with PTC is rather boring. They don’t even get hot. That being said, cheap noname chinese cells don’t have a PTC. Nor a CID, nor any other internal protection feature. Luckily, their capacity and current performance usually is so low that they don’t vent even in a dead short. I’ve tried that a few times.
A bigger danger is an INTERNAL short due to lack of quality control (as Angler pointed out). At an internal short, all the current goes through a very small area (where the defect is), so it can reach separator breakdown temperature and then ignition temperature there. At an external short the current (and thus temperature) is (more or less) evenly distributed over the whole cell.

The PTC is not the protection board. It is an internal part of the cell safety mechanism, not removeable. To my knowledge these cells without PTC are only made for Tesla.