Samsung 25R's (blues) discharged to 0V

[Izen]

New one for me... mod stopped working and I realized I'd over-discharged my batteries. I usually pull them when they're down to around 3.4 volts. The display isn't in my face, I have to throw a switch to see, and it was reading 5.25V for the (series) pair. Put 'em right into the Nitecore UM20 charger. Both showed 0v on the display... Almost immediately one of them started to take a charge the other sat a zero. After not even two minutes one was reading 2% the other still at zero... so I decided to pull them both out of the charger. Fuck it! I'll trash 'em. Don't want to take any chances. I usually check the battery status more frequently but I just let it get away from me this time. Was too busy sampling new e-liquid. Live & learn.

Am I doing the right thing? Or, should I attempt to revive? --- Just curious, but I think I know that disposal/recycling them is best.

 

[Zamazam]

you can revive them on that charger. give it another shot.

 

[Izen]

you can revive them on that charger. give it another shot.

Thanks man! but you sure about that? Haven't they been compromised? I admit though, I don't have much experience with this.

 

[raymo2u]

Samsungs are pretty heavy duty 18650's...Ive done things with them I wouldnt try with any other battery except some LG HB6's...Ive yet to see one go thermal either. Ive vented as an experiment but its was a hard short and it took awhile

 

[smacksy]

Thanks man! but you sure about that? Haven't they been compromised? I admit though, I don't have much experience with this.

I've had my charger read 0 after running my batts down, but I just rolled the battery around in the slot to make better contact, and when she started charging I let them charge all the way up..they're working great..

Sent from my QTAQZ3 using Tapatalk

 

[Izen]

Ok, thanks guys. Just took your (3 out of 3) advice and threw 'em both back in. They were both in the charger for about 2 mins before I posted... Now when I put 'em back the one that was at 2% showed 18%. The one that was at 0% showed 4% ...so I guess they'll live to work another day. Thanks again !!!

 

[fq06]

A regulated device won't let them get to zero, maybe lower that you want to take them like 2.8 but they will be safe.
Mainly what happened is some life span got taken out of them.

 

[Izen]

A regulated device won't let them get to zero, maybe lower that you want to take them like 2.8 but they will be safe.
Mainly what happened is some life span got taken out of them.

Thanks. That's what happened. The VV series box mod cut-out and didn't fire. When I checked the voltage it was about 5.75V (series /2=2.875)... but they showed 0% & 2% when put in the charger. Never took 18650's down so low so I posted for advice (as long as I'm here... why not?)

My other two regulated mods have displays that might show the battery depleted, and the mods won't fire... but the batteries will show about 25% - 30% when put in a charger,

 

[fq06]

Oh, in that case you can take some serious life out of the cells and internal resistance rises considerably when you drain the cells so much that it barely fires. They will fire a little weaker going forward so once your vape starts to lose it's gusto it's better to just stop (usually happens about 3.5v) and deal with the lack of nic till you get home rather than damage your cells.

If you're handy you can add a LVC beeper for rc models.

 

[Izen]

@fq06 - Re-edited my last post so i don't know if you'd seen it all. Appreciated the comment though. I usually pull the batteries at 3.4 to 3.5 volts. Mfg recommends no lower than 3.3v... I just need to periodically check the DVM. The mod did cut out at about 2.8.

 

[fq06]

Right on, you've got it handled. I still like the idea of a little buzzer that'll trigger ~6.4v

That's how we had to do it before rc speed controllers had LVC built in or you would suddenly lose a bunch of power and your lipo pack went from a race pack to a practice pack... at best.

 

[dr_rox]

I do not have that charger, but if the mod shut off and you put batteries in charger, there is zero percent useable CHARGE, NOT ZERO VOLTS on the batteries.
You also stated percent charged, not volts.
Just thinking out loud.

Having charger set to read volts is more informative than reading percent charged.

One other add - a mod may shut down not because voltage is low on batteries, but it cannot deliver the CURRENT load because of internal resistance of the battery(s) and load of circuit. So, when you put it in a charger that determines % state of charge based on voltage, it will not agree with what mod reports.