> On 12/22/2022 4:34 PM CST Chuck Guzis via cctalk <cctalk@classiccmp.org>
> wrote:
>
> That's not to say that Li-ion cells are without their quirks. I
> recently almost discarded a AA-sized 14500 cell because the output
> voltage had suddenly dropped to the point where none of my chargers
> would even see it. So I put it on a corner of my workbench against the
> time when I had accumulated several and could turn them in for
> disposal. A couple of days ago, I picked up the cell and checked it
> with my voltmeter and it read 3.5V. Put it in the charger, and slowly
> charged to capacity. What happened during the month or so that it sat
> on my workbench, I cannot say.
>
> --Chuck
A VERY large percentage of LiIon batteries have a protection circuit built in
to prevent over-discharge. Even a lot of the "standard" cell types (e.g.
18650s) The circuit disconnects the battery from its terminals if the voltage
drops too low, showing near 0 volts out. If it just barely meets the cutoff,
it may recover enough to re-activate the circuit, making it possible to
recharge it. Often, you can open the case, skip over the circuit board to
access the battery cell directly, and add a small amount of charge to
reactivate it. Then it will work normally. I've done this a few times.
Will
I do not think you can name many great inventions that have been made by
married men. Nikola Tesla
