Doh! Don't leave 10440 sitting in nano charger when not in use ...

[selfbuilt]

Sigh ... made the mistake of leaving a fully-charged 10440 sitting in its nano charger holder when not in use (bought from AW here). Went to try it today, and it wouldn't start. Measured the voltage, and it has dropped to ~0.4V!

Seems it discharged through the inactive charger while sitting in my drawer over the last couple of weeks. Guess that wasn't the brightest idea! :shakehead

Oh well, at least the nano charger still seems to be working ... although I'm not sure if I should still trust it. Time to get a new set, I think ...

 

[Groundhog66]

I did the same thing last week.


Tim

 

[Argon]

I have completely drained a 10440 in my lod-ce once by accident, went to use it but it was already switched on and when i tried to turn it off and on again i got nothing. i figured the cell was dead. But i left it for a few days it seemed to of recovered it self, when i measured it, it was at 2.7v so i figured may as well see if i can charge it back up and it seems the cell is back to normal.

I have also left the cell in the nanno charger for a few days while the green light is on and it seems to have no ill effects.

 

[DM51]

I have completely drained a 10440 in my lod-ce once by accident, went to use it but it was already switched on and when i tried to turn it off and on again i got nothing. i figured the cell was dead. But i left it for a few days it seemed to of recovered it self, when i measured it, it was at 2.7v so i figured may as well see if i can charge it back up and it seems the cell is back to normal.

I have also left the cell in the nanno charger for a few days while the green light is on and it seems to have no ill effects.

You were lucky with this cell - it could have exploded when you recharged it. Be very careful with it from now on, and if it heats up during charging, stop the charge and get rid of it. Personally, I would not use it any more.

Also, if you leave a cell on a nanocharger after the light has gone green, there is a danger that it may be overcharged. A 10440 cell is not protected from over-discharge or overcharging, and you are asking for trouble if you don't treat it with care.

 

[Groundhog66]

Mine went directly to the recycling.

Tim

 

[Thujone]

The over discharge protection in my LF2 has been working flawlessly... Warning at 3.0 shutdown at 2.8

 

[DM51]

The over discharge protection in my LF2 has been working flawlessly... Warning at 3.0 shutdown at 2.8

Yes, but that is a feature of the LF2 itself, not the cell. There are no protection circuits made small enough to fit on any 10mm diameter cell.

 

[Thujone]

Yes, but that is a feature of the LF2 itself, not the cell. There are no protection circuits made small enough to fit on any 10mm diameter cell.

That was meant as a little poke at the L0Dce.. For $45 the LF2 has an incredible amount of features, and at 7800hz the PWM is completely unnoticeable.

 

[selfbuilt]

Yeah, I'm always very wary around charging/discharging Li-ion, especially on these unprotected cells. My depleted cell went right into the battery recycling box.

But I thought I'd post this so that others realize not to leave a Li-ion sitting in a disconnected charger when not in use. Obviously, anything that can charge a cell can also discharge it (even with no external current applied).

Just to be on the safe side, I've ordered a replacement set from AW and will toss the old nano charger out, just in case.

Be safe everyone ...

 

[Argon]

You were lucky with this cell - it could have exploded when you recharged it. Be very careful with it from now on, and if it heats up during charging, stop the charge and get rid of it. Personally, I would not use it any more.

Also, if you leave a cell on a nanocharger after the light has gone green, there is a danger that it may be overcharged. A 10440 cell is not protected from over-discharge or overcharging, and you are asking for trouble if you don't treat it with care.

I know and understand the risks involved with mistreating lithium ion cells i was rather surprised that this cell is still working, it has since been through another 5 or so cycles. I also have never noticed any overcharging in the nano charger even when the cell was left in it over a few days with the green light on. I have also never noticed the cell heat up much while charging. maybe i've just been lucky with this one though.

When this one finally expires i'll order some more from dealextreme.

 

[Lite_me]

I feel like my Nano charger is easy on my cells too. If I remove the cell when the light turns green, it reads 4.12v. If it leave it on the charger for another hr. or two, it registers 4.16v. I've never left it longer than that but I don't feel like it would over-charge. I'm very happy with it. It's small and convenient. I should get many cycles from my 10440s with it.

I knew not to leave a cell in it unplugged. Seems like common sense. I also doubt if leaving the battery in it while unplugged hurt the charger any.

 

[selfbuilt]

I knew not to leave a cell in it unplugged. Seems like common sense. I also doubt if leaving the battery in it while unplugged hurt the charger any.

Yeah, it is common sense - I was surprised when I opened the drawer to get the charger and saw I had accidentally left one in there (my charged Li ions usually all sit in a separate Pelican case when not in use). My point for posting is to alert those who might not have given it any thought ...

I suspect the charger is fine, but all that stored power had to go somewhere, and I don't know how well the charger can handle accidental discharges through the unit. Don't want to potentially compound an error by finding out.

 

[9volt]

Thanks for the tip, I read this and realized I have a 10280 sitting in an unplugged Nano charger. It appears to be completely drained, doh! I guess I'll pitch it and get another.